It's been many years since I looked at YI hacking. Editor limitations were one reason, so I thought I'd check in now that I've heard about a new editor.
The emulator restrictions make this unappealing, though. It feels like it'd seriously limit any hack's audience. A lot of people won't bother downloading a new emulator just to play a hack (as I've seen in other hack communities, when an essential tool forces hacks to be played on a specific emulator)... and does it even support however SD2SNES runs SuperFX games, for the players who never use emulators? I've encountered many such players in the SMW hack Twitch community, so it seems important to account for them.
Have you considered support for the GBA version?
It's almost a direct port, but on a console that supports much larger ROM sizes, and no more SuperFX limitations. The level format is nearly identical (just 4 bytes per sprite instead of 3, and some bit-shifting in the header), so all vanilla edits should port over easily; I was able to document the differences back in 2010
, when I had no ASM knowledge and several header bits were still undocumented. 8-bit sprite set IDs instead of 7-bit should even allow every sublevel to have its own sprite set without extra coding. I'm aware the Better Middle Rings patch wouldn't immediately port over, but if porting it is an issue, I don't think the vanilla 4 middle rings per level, in an expanded table that gives every level the full 4 slots, would be very limiting?
Edit: I also looked at the Better Middle Rings patch, to see how complex it might be to port over, and for some reason it forces all entrance types to be 0? Midway entrances can
use nonzero entrance types, even though they're not used in vanilla, so I don't think an editor should forcibly remove support for that. It allows for checkpoints on skis, among other things.
Alyssa's Unlikely Trap (demo 3)