I'm going to be away for the next couple of weeks, so
here's a WIP. I'm up to the third boss, which I'm currently redoing because I found a way to beat it much faster. There are some spots in the tutorial and one of the underwater levels where there might be simple improvements, although I haven't checked for sure and I have no idea if it would be possible to hex them in. Currently, I'm about 50 seconds ahead of the test run, and probably much more than that after the next boss.
I've also been looking for useful RAM addresses, with little success. I found a few locations that clearly have
something to do with Sonic's movement (they're 0 when he's standing still and they're usually other things when he's moving), but I can't make heads or tails of them. Whatever the system is here, it's beyond my very limited knowledge.