Ah, somebody had the guts to go and do it!
I do have a few suggestions and complaints
1. No Spindash Animation? I know it's possible with Jecks, looks like you went over it.Kind of an odd choice to leave out?
2. The falling frames kinda proves an issue I was having... most of your animations are based off the stiff Stay-In-Pose-With-Spike-Movement idea from SA2, which looks a little awkward with the posing SA1 had with the little movements on the legs and arms and such. I know it's a pain in the butt to do, and might not work due to how SRB2 models work but add some more motion to those Stay-In-Pose-With-Spike-Movement animations. Makes it more lively
Other than those, model is great! Wouldn't be opposed to more of these