To thank all you folks for your continued patience, and to prove that I'm doing something, here's the very first sex scene I managed to do that doesn't look like complete garbage!
It's neither perfect nor final, as you can see from the lack of background for example, as well as a number of minor faults I still need to fix, but I think it's hot, and this does make me confident I've broken through the worst of the difficulties. Sex scenes were one of the big barriers that made me quit for a while; it is VERY HARD to wrangle AI to make convincing-looking scenes between two specific characters.
I'm probably going to do most sex scenes in this "POV" style, both because I don't think most people are in it to watch Sonic fuck, and because it just works better. Also I made Sonic's dick flesh-colored. AvalonX made it blue, but I tried blue and it looks very strange. If you really want to make an impassioned plea for blue-dick Sonic now's your chance.
Criticisms welcome as always, if there's anything you don't think looks right, the earlier you say something the more likely it is I can fix it before it gets locked in!