That is seriously awesome, thank you.
And no way, my Pikachu/Raichu is one of my favorites too. That's why I hacked Yellow!
Considering the 'few pokes will actually be made main starter issue', one thing I was actually thinking of is trying to create some 'generic' emotion sprites, akin to Soulsilver/Heartgold, and having an all pokemon follow hack. However, all pokemon follow hasn't been coded yet. I think it's very doable though. I'm not sure if non-generic emotion sprites really count as devamps as I don't remember them in future versions, unless you count Mystery Dungeon which did have them. (which, hmm, yeah, could be useful for Mystery Dungeon mimics, no idea how hard that'd be to code on Yellow or if anyone would try; I only remember the one Mystery Dungeon remake hack for Ruby.)
Eevee, Meowth, and Pikachu I think are the starters most likely to be used for solos, maybe Dratini, Scyther, Vulpix and Growlithe too, and we've already got Pikachu down. :3 Eevee is really the biggest one after Meowth (who is must for Team Rocket hacks) I see people using though, it's so incredibly popular and could be used for a 'play as Gary' hack. Trying to decide how to handle evolutions sprites for it would be a bit of a pain though... although probably you'd use the happiness gimmick and have evolve by happiness, which still leaves three choices, Umbreon, Espeon, or Sylveon. No night system mean Umbreon is out. Although, is possible the game might have enough room for extra emotion sprites for all the Eevee-lutions and checks for species could be coded to load the right emotions. Would be a bit of a pain, but, theoretically doable. I have to admit, I'm glad you didn't say your favorite pokemon was Eevee, lol.