See, the three gameplay styles you mention definitely need major work, but if we're supposing that a remake would make substantial changes to the gameplay like that, then I think we ought to focus our demands elsewhere (at least at first). Like Sonic's gameplay. If they remake Adventure from scratch in 2020, or later, they'd have no excuse for it to not have a complete Sonic physics engine this time. Also give Sonic back the ability to curl into a ball (without using the Spin Dash), like Tails and Knuckles still have. Removing mechanics can make for interesting followups, if done right; I don't think taking the billiards out of Sonic's platforming was "doing it right" (particularly since adding billiards to Mario was how they made Sonic in the first place), and having done so is probably the greatest blight on the entire game's design. In lieu of improvements like these, none of the bug/camera/visual improvements endemic to a typical remake would really matter to me; none of it would really make the game much more fun to play. I'm used to the bugs and camera already, I imagine I can mod the game if I want it to look nicer, and I can just not play the parts of the game I don't like when I go back for short sessions.