OK. So this has already greatly exceeded my expectations -- in particular the support for the GB printer and the initial SGB border for supporting GBC games are things I wasn't expecting. This is quite clearly the definitive emulator for GB games right now, at least on DS (and still better than playing GB games on 3DS VC because *color*).
I was curious about the viability of a couple features. In a couple backward-compatible GBC games, such as Wario Land 2, Pokemon TCG, and the Game and Watch Galleries, the Super Game Boy border is somewhat dynamic, changing in the first case based on which level is being played and in the second on which badges the player has collected. Since I don't know of any emulator that's even tried to implement this as a feature (except for possibly bgb? and even then they admit it's pretty buggy if it's what I'm thinking of) it does seem like something that would probably be completely unfeasible. I can't say I'll be particularly miffed if this can't be done, since having even the static initial SGB border is more than I expected, and outside of the game and watch classic mode borders they're usually not much to write home about.
Other feature I'm curious about is probably a bit out-of-scope but is something that has been done in at least some emulators before, though not ones focused only on GB stuff -- implementing SGB enhanced sound for games that support it, like Donkey Kong or Animaniacs. I have no idea if there's a quick-and-dirty hack that would make this possible without having to build an entire SNES emulator though, since I know embarrassingly little about how the SGB actually sends that enhanced sound data to the SNES. (Hell, I'd probably buy the argument that there just isn't space in RAM for the samples in question.) The lack of it is more frustrating to me than the previous issue though, just because otherwise, say, Animaniacs is a choice between color OR sound, and damn if I don't love the little "help help" sound in Donkey Kong.
Even then I still see these as "might be nice to have" more than "necessary to keep games from being broken" sorts of features.
I was curious about the viability of a couple features. In a couple backward-compatible GBC games, such as Wario Land 2, Pokemon TCG, and the Game and Watch Galleries, the Super Game Boy border is somewhat dynamic, changing in the first case based on which level is being played and in the second on which badges the player has collected. Since I don't know of any emulator that's even tried to implement this as a feature (except for possibly bgb? and even then they admit it's pretty buggy if it's what I'm thinking of) it does seem like something that would probably be completely unfeasible. I can't say I'll be particularly miffed if this can't be done, since having even the static initial SGB border is more than I expected, and outside of the game and watch classic mode borders they're usually not much to write home about.
Other feature I'm curious about is probably a bit out-of-scope but is something that has been done in at least some emulators before, though not ones focused only on GB stuff -- implementing SGB enhanced sound for games that support it, like Donkey Kong or Animaniacs. I have no idea if there's a quick-and-dirty hack that would make this possible without having to build an entire SNES emulator though, since I know embarrassingly little about how the SGB actually sends that enhanced sound data to the SNES. (Hell, I'd probably buy the argument that there just isn't space in RAM for the samples in question.) The lack of it is more frustrating to me than the previous issue though, just because otherwise, say, Animaniacs is a choice between color OR sound, and damn if I don't love the little "help help" sound in Donkey Kong.
Even then I still see these as "might be nice to have" more than "necessary to keep games from being broken" sorts of features.