Honestly, from the past behavior and the 'sudden return' several months back, I don't think he'd do anything.
Sure, I could fantasize that he could possibly....
Add more actions while fixing some of the others(Such as an improved swimming cycle and whatnot)
Improve maps
And in general, just,adding more to the character creator. Maybe even adding a new species or something.
But honestly, I doubt he'd ever do that, since he's openly stated he doesn't take responsibility for Feral Heart anymore.