Option 5 would do well if there were enough artists around to contribute. If we're talking about completely new graphics, I can't see that happening. If we're talking about compiling a tileset from existing graphics plus new ones, that's more likely but still seems very ambitious. However it would be awesome to see a new tileset be completed.

I myself am most comfortable using Pure first, GameBoy second. I feel like they're a little more difficult to use, but with them there is more variety to work with than in classic derivatives or something like BS or NewFirst.