MkA would have been the time to do that, but nope.

I don't wanna see the elder gods as playable characters. Maybe a glimes at them in an opening video, but that's as far as I would ever go with that.

The Elder gods will not be playable for the same reason Raiden is annoyed with them. They refuse to involve themselves with the dealings of mortals and lesser beings and believe that such entities should settle their own matters themselves. They only get involved if they themselves are at risk and even then it's not first hand and direct - see MKD.

Effectively it equals to the US shadow council behind the Bush administration sort of... the oil lobby being only a small fragment of it...

Other than that, ther Elder Gods remind me too much of Lovercrafts Elder Gods that are universally ambivalent to the makings of mortals.

I would like to see water and fire gods

A new elemental? That would be pretty sweet, if they have a good reason for it.

On the 2nd mortal kombat movie, there was four types of gods. Fire, Water, Earth and Wind. I've heard that there is bout 12 elder gods.