1) Character Variants
2) Incorporate Elements From The Mobile Version
3) Replacement Characters
To start this point I want to say spoiler alert. Anyway for those who played the first Injustice;s story mode you know not everyone makes it out alive. Shazam gone there needs to be a new champion of magic, With Wonder Woman dethroned there needs to be a new maiden of might and so on. This was sorta explored with Damian replacing Dick as Nightwing after his death. So why not expand this a bit; let Bruce retire, Roy take up the bow, or Cassie become Wonder Woman. Conversely how about have old heroes characters become new heroes, something the arcade mode alluded to. Examples might be Barry, Hal, and Harley seeking redemption by shedding their tainted mantles. All of this would simply be cosmetic in standard play, but in story mode could make the characters all the more interesting.
4) More Diverse Roster (AKA Less Batman)
5) Powerful Super Baddie
What made the threat in Injustice do great is that Superman is in fact more powerful than the other heroes. Now with him behind bars, a new villain needs to take his place. The obvious choice would be Darkseid, but perhaps a less obvious choice could also work, maybe another hero snaps, or an obscure villain becomes exponentially more powerful (maybe Atrocitus takes advantage of the Lantern imbalance and seizes power).
In a perfect world, we would see the roster simply expand, but that can't always be the case so here is the list of everyone I want to see in the future, obviously DC's trinity is a must so I won't include them.
1) Red Hood
Another member of Superman's rogues gallery, and my personal favorite DC villain. Brainiac can match Superman as a fighter while his intellect could make could make for interesting play styles. Not only that but his technology could make for some great combos.
Everyone else I want were already in the first game, so I won't list them. Although there are some interesting skins I think would be cool; perhaps the insurgent Harley Quinn becomes the new Nightwing/Robin/Batgirl, Red Arrow, Green Lantern Aya (not sure how to work her into the story), Tim Drake, Kyle Raynor, Eradicator...It's an easy way to increase the roster and introduce players to new characters.
Do you agree, disagree, or have an idea for what you want to see? Feel free to leave a comment below.