MK has one of the best storylines when compared to other fighters, but gameplay-wise, it is usually low on the list.
Considering only the first two games were tournaments, and the rest have been wars, why not make the new games role-playing adventure games?
Think about it; you take control of one of the heroes/villains, and as you progress through the story, you meet up with other characters and add them to your own party, making them stronger with special items (perfect example: Sub-Zero receiving the Dragon Medallion), and learn new abilites through leveling-up.
Fatalities cold be performed on the last opponent standing in the enemy's party, maybe add a combo system when close to an opponent, and make use of the mini-games more effectively by adding prizes other than Koins, like weapons, or armours.
Imagine the kind of boss battles that there would be; seeing the sorcerors like Shang Tsung and Quan Chi showing off their true abilites and powers, or people like Shao Kahn and Shinnok, who are supposed to have god-like abilites actually using them to take on your party.
If MK would become an RPG, most of these features could advance the storyline and put things into greater detail than they already are, and the game could probably take in a new generation of RPG-loving players, as well as players of the series who think that MK's destined to be more than a middle-classed fighter.
What do you think?