This is a pretty neat recreation of SRB1 Sonic, I like it! Though, it'd be nice if you could also bring back Super Sonic as he was playable in SRB1 Xmas, and had Earless sprites. If so I think his color should be on the sprite instead of as a super color [to match how his colors were animated in the original], as well as transforming with Jump instead of Spin, with no animation or music.
Excellent recreation of SRB1's gameplay. His janky gameplay makes him really interesting and challenging to play. Though, doing a full game run will turn each stage to "How many lives can you get" to prepare for the boss fight. Though I personally find that fun, so it's not much of a negative in my book. Only suggestion I can make is to make his rings collectable, as hard as they can be able to get. This would make boss fights a lot easier.
This dude is just, so goofy to play as, I love how the jump physics and instant acceleration emulate the movement from the TGF games, the killing dead thing is a nice touch but the lack of a recovery option means bosses can be a pain to deal with even if you don't get hit by attacks, since you may die from simply hitting them instead. Either way, he's a fun character in his own way, and you've done a good job at recreating that 1998 gameplay.