I haven't kept up with comics in a while but the concept sounds interesting and certainly hews closer to the Jekyl/Hyde dynamic.
Do you remember this David story?
I know they ended up going back to this idea of the Dark Matter Sorcerer Supreme attaching itself to Gray Hulk. In the original story the way to get him out of Banner was to go into the psychic plane of Bruce's mind and to attempt to unleash the Green Hulk. Well... If anyone disliked the smart Hulk of AEG, here's a way to get more into Bruce's MPD issues and bring back Green Hulk and perhaps get into the Gray Hulk (perhaps utilizing some of that Immortal Hulk angle rather than the pure Joe Fixit material which, let's be honest, needs more set up and time than the movies allow), all by using Dr. Strange's powers to facilitate it. You can have Bruce be taken over by the Dark Matter Sorcerer and this forces Strange to have to bring in all the other heroes. The resolution then brings Banner back to having to share his life with "the other guy" and maybe... Another guy? Now back to having to deal with the instability of his pre-Avengers life, Bruce must take refuge within the Sanctum.
Just spitballing here.