Eternal Darkness, given a new coat of paint and spruced up game systems could be interesting. The insanity concept would need an overhaul; very cool idea that in retrospect wears itself out and definitely relies on gimmicks that are transparent all these years later. Tweaking that basic idea could lead to interesting things. Story is still very strong and the overall narrative arc has some killer moments and callbacks.
Vampire: Bloodlines, I've been arguing for a long while. The ship might have sailed as mass market immersion sim popularity seems to have passed the rejuvenated spike and now dwindles, but as Deus Ex, Dishonored, Prey, and all that do well enough Bloodlines is primo game design for a remastering. Tail end of the game and some of the blatantly broken chunks would need reworking, but it's otherwise a superb action RPG / immersion sim that I feel ticks a lot of boxes (particularly in character and story) that people enjoy about AAA games.