I mean since were looking at a time when sorcery and other worldly forces were probably more widely accepted ithink it would be cool to see the ancestors of some of the MK crew. you could have maybe an actual outworld born cryomancer, and still have a lin kuei assassin. you could have a shirai ryu ancestor that was similar to scorpion without being a carbon copy. because kitana is 10,000 years old you may even get to see a teen version of her. Shang Tsung in his actual youth. Goro of course. Raiden. a Mercenary like kano or a brigand that figts with knives. I mean the list of possibles can be pretty extensive seeing as how there is a lot of room for new or reimagined characters
You're right about ancestors of Sub-Zero & Scorpion.
For the Forces of Light:
Kung Lao I - like Liu Kang
Raiden, god of Thunder
Fujin, god of Wind
Suijin, god of Water - before Rain
Inari, goddess of fertility
Bo'Rai Cho
A samurai - like Kenshi or way before him
A thief - like Johnny Cage
An exiled guard - like Sonya
An knight - before Stryker
A witch (a kitsune) - before Nightwolf
A cryomancer - before Sub-Zero
A Shirai Ryu - before Scorpion
A strong man/viking
A pirate
...and the Forces of Darkness:
Shao Kahn
Shang Tsung
Quan Chi
Shinnok
Kitana
A killer/prisoner - like Kano
A succubus - like Mileena
A saurian - like Reptile
A barbarian - like Baraka
An amazon
An Egyptian
The neutrals:
A Lin Kuei - before Smoke, Cyrax & Sektor