In addition to skins and new characters, why doesn't NRS do different story campaigns outside of the MKX main story as DLC? I think if you're not going to do an actual Konquest Mode for an official MK game, mix it in with the actual MKX fighting mode in a DLC story campaign instead. That way you could explore other realms and fight numerous NPCs rather than solely on the MKX fighting mode where it's kombatant against kombatant. Plus they could do stories that happened during MKX, but never had the chance to appear in Story Mode or events BEFORE and AFTER MKX. I have a few ideas:

1) The Search for Liu Kang (AXED IDEA)- After Dark/Fire God/Shinnok-Possessed Liu Kang (I don't know we don't know what happens to him as he has not been shown yet) gets defeated near the end of MKX (that's just my prediction), he somehow gets his old character back before being indiscriminately being sucked back into the Netherrealm. The campaign takes place after MKX where you can play as the trio Kung Lao, Kitana, and Nightwolf who travel back to the Netherrealm, investigate his whereabouts and fight the last remnants of the Brotherhood after Shinnok's/Quan Chi's fall until they find out Liu is not being kept in Netherrealm proper, but a realm within a realm called Diyu, the Chinese version of Hell and have to rescue the Champion of Mortal Kombat to hell and back. Enemy kombatants include Kia, Jaakata, Drahmin, Revenant Mileena and Baraka, a revamped version of Diyu denizen/rumored character Belokk, and Tanya cameo. One MK veteran's life will finally come to a sad, but fitting close (permanently you know like most of Reptile's race, King Jerrod etc.).

2) Rise of the Cryomancer- If it doesn't make it in the comics, play as Kuai Liang to retake the Lin Kuei from Sektor and Cyrax with a playable assistance from the Netherrealm succubus Sareena.

UPDATE: The comic subplot will be flashbacks while the main story will be the aftermath of MKX after the Lin Kuei successfully repels Kotal Kahn's forces back through Outworld. Sub-Zero returns to the Lin Kuei Temple to find it under attack by Red Dragon with Frost fighting them. In the middle of the battle, Sareena appears in her monstrous true form and annihilates most of them. After their victory, Sareena reunites with Sub-Zero and presents him with shocking news that his brother Noob Saibot has survived and is gathering an army to invade Earthrealm. She also gives Sub-Zero written material she took in the "Out of Hell" DLC story arc, revealing the location of Sub-Zero's forgotten race, the Cryomancers. Along with Frost (some cutscenes shown to highlight both their conflicted yet respectful master-student relationship, Sub-Zero's calm demeanor and Frost's aggressive nature), Sub-Zero sets out to the frozen northern reaches of Outworld where he encounters undead frozen warriors, mountain predators, and a final boss battle with a mysterious Cryomancer possessing the Deception Shredder armor. After fatally wounding him, Sub-Zero unmasks the armored Cryomancer, revealing much to Kuai Liang's horror to be his and Bi-Han's father who left the Lin Kuei mysteriously, leaving Bi-Han to take the codename Sub-Zero as a family honor in his flashbacks. Kuai Liang's father apologizes for kidnapping both of his sons from their mother under threat by the Lin Kuei. The father said his faith in the Lin Kuei was shattered over this ordeal and left his sons immediately to the clan not wanting to subject them himself to their harsh conversion to assassins and facing their distraught mother. He thought his sons would grow up and eventually find out about their father and come looking for him in Outworld when the time was right. When the father finds out about Bi-Han, he begs Kuai Liang to try saving his brother from darkness and blames himself for Bi-Han's ruthless nature. Before he dies, Sub-Zero's dad whispers inaudibly into his son's ears over the whereabouts of his mother and possible siblings. Sub-Zero, in grievance gives his father a frozen burial and takes his father's armor in honor of his army. In the end, Sub-Zero and Frost return to the Lin Kuei Temple and asks assistance from the Shirai Ryu, preparing them for Noob Saibot's Netherrealm onslaught in MK11.

3) The Way of Chaos- Play as Noob Saibot after the Soulnado lands him in Chaosrealm so he can explore and be under the employment of Havik, the Cleric of Chaos where Noob can sow havoc in Orderrealm with his asshole behavior and even make enemies with Hotaru. It is also where Noob can meet a female Chaosrealmer and decide to settle his new life in Chaosrealm with her. The offspring that might result from their relationship will definitely be one of the MK characters even after the relationship is short-lived due to Noob's cold behavior and opens up the events leading to Chaosrealm invading Earthrealm with Havik and Noob's potential as a boss character in future MK games. There can also be playable flashbacks where you play as Bi-Han, the original Sub-Zero between the aftermath of Mythologies and the beginning of MK1.

4) Lost Souls (AXED IDEA)- It's a separate dual playthrough. Play as freed Ermac in Outworld after MKX as he tries to seek answers about his past with the assistance of Bo' Rai Cho while meanwhile in a different storyline Reptile in Outworld is trying to find the last remnants of his race after the civil war and meets up with Khameleon at the end. Along the way both characters are fighting Mileena sympathizers, Shokan Rebellion gangs, and other dysfunctional Outworld groups. Cameos of Li Mei, Nitara, and Bo' Rai Cho can appear in the DLC storyline. Also both characters battle one common new faction: the Lava Shrine Priests who are led by "Ryu Naga," a mysterious imposter claiming to fulfill the prophecy of the Dragon King's return.

5) Children of Edenia- In the aftermath of MKX, Queen Kitana (or not yet), who is now in contact with Delia, the wife of Argus as her disciple if my hypothesis in that other thread comes true, asks Kitana to awaken her son Taven against her husband's wishes in order to combat Daegon, the rogue brother who is still threatening Earthrealm with the Red Dragon and might fulfill the One Being's return. After freeing him, you can play interchanging as Taven and Kitana while you can experience both their interesting and heartfelt conversations (something that Armageddon never did with Taven is interacting with important Edenians like Kitana and Sindel) as they both travel to the Lin Kuei Temple so Taven can retrieve his mother's gift (the armor he wears) after Kitana tells him that his father's gifts were taken by Daegon so he doesn't have to travel to the Botan Jungle. In the first part, Taven's awakening spot is near a volcanic vent underneath the Himalayas where the Lin Kuei Temple is situated. In this new environment, I could give Kitana a battle parka to fit the climate somewhat of a mix between Lara's "Rise of the Tomb Raider" and 2003 Star Wars Clone Wars cartoon Padme Amidala's parka. Along the way they get ambushed by Rain who is hired by Daegon to slay Taven for a bounty and muses he'll get double once he sends Kitana's head to Tanya and even reveals a bit of backstory as story material pertaining to the Edenian theme. In the end, Taven tears off Rain's arms to prevent him from using water powers while Kitana, disgusted with Rain's misogynistic behavior and his treachery, clips off his GENITALS, sending a humiliated Rain back to Charred Mountain where furious Daegon throws the armless and ballless Rain into a pit where Human-Dragon hybrids tear him apart, ensuring Rain dies for good. After getting a pass into the Lin Kuei Temple by Sub-Zero where because of Kitana's presence there's no fight, Kitana parts ways with Taven through a portal back to Shang Tsung's Island where her people are currently resettling according to my hypothesis in another thread citing Taven must be able to deal with Daegon for it's a personal matter for him in which she says she has no business being involved and that she is fully confident Taven can handle himself. The second part of the DLC has Taven teleported to Charred Mountain where he meets up with father-and-son duo Kenshi and Takeda where they happen to encounter dark sorceress Tanya who wants to test Taven's skills and leaves halfway through the battle ensuring that they'll meet again along with spilling backstory exposition about her and trying to convince Taven that KItana is the enemy he should be fighting, not her, but Taven is not fooled by her temptation. At the end Taven has his inevitable fight with Daegon and the whole Daegon turning evil story is revealed where it all comes down to an emotional climax. I'll just leave it to that.

UPDATE: Since Kitana has not turned out alive as I predicted in MKX, most of the ideal precepts and the plot are going change, but Taven will be still be playable and have an important role in the DLC prior to his playable appearance in MK11 if the prediction comes true. The new Edenian in place of Kitana is Jade who has a very potential comeback in MK11. In my DLC before she was assigned in the First Netherrealm War, she was rescued and resurrected by the Purple Lady in Outworld, explaining her absence with the revenants. Given visions of Kitana in her old timeline, she is assigned by the mysterious figure to free Kitana who is now Queen of the Netherrealm with them. In return, Jade is given shocking details of her forgotten heritage by the Purple Lady. After the Lady disappears from her mind, Jade throughout the DLC wanders as a Bedouin-like sandal wearing wanderer in sidequests fighting Tarkartan hordes, Black Dragon and Red Dragon thugs, freeing Outworld villages from oppression, collecting bounty on poachers and human traffickers, and being in conflict with the Edenian Resistance run by Tanya. Cameos include Erron Black, Reptile, Nitara, and a surprising appearance from Shang Tsung. Meanwhile Taven's slumber is disturbed by Red Dragon thugs and he awakens, fighting them in the first leg of his journey. He encounters Sonya, Johnny Cage, Li Mei and her Outworld refugee fighters, and the Kombat Kids who are retreating from Daegon's terrorist attack on SF Headquarters and hiding within a secret underground bunker in the Rockies. Taven helps SF by annihilating the incoming Red Dragon legions until they retreat through a portal to Charred Mountain where Taven follows. There he finally comes to his dark reunion with his little brother Daegon who wants to kill him. At first Taven does not want to fight him, but Daegon persists, assaulting him until Taven gains the upper hand, forcing Daegon to flee in a plume of flame. Caro then tells Taven his little brother's tragic story and the deaths of their parents Argus and Delia. Taven develops his guilt, feeling responsible for Daegon's downfall for not awakening around the same time as Daegon in order to save him and prevent his parents' deaths. Caro tells Taven to retreat to Outworld through a portal where he can gather allies and an army to face and stop Deagon once and for all while Caro stays behind to fend off the last remnants of Red Dragon remaining in Charred Mountain. Playable flashbacks from both Taven and Jade's pasts as children will be revealed in a pre-invaded Edenia giving character context to both the protagonists separately. DLC ends when Taven crosses paths with Jade during a Tarkartan attack under orders of a new unseen Tarkartan leader (possibly revealed as a new character in MK11). After their victory, Taven and Jade join forces in order to complete their objectives in MK11: gather an army possibly the Edenian Resistance, return to Earthrealm, defeat Daegon, and free Kitana and the other revenants from the grip of the Netherrealm. Out of Hell: Play as Jax and Sareena to move your SF forces out of the Netherrealm, while fighting off revenants led by Emperor Liu Kang and Empress Kitana and exploring Netherrealm planes like the city of Nekros the Pyramid of Shinnok (location from MK: Mythologies Sub-Zero) as a possible gateway back home. Sareena gathers some material relevant to Rise of the Cryomancer near the end and overhears intel that Noob Saibot has immersed from Chaosrealm, gathering an army and discovers the disturbing truth behind his identity.