I like the ones that are already there, but I think Nintendo really needs to hurry up and start making more classic Game Boy games available, as well as get some decent third party support for the service.
I think that Nintendo should make other titles up to the SNES era as well as covering all the handhelds. If Ambassadors can get GBA games, then really everyone should despite their stance on not doing so. And SNES games are do-able since the remake of Yoshi's Island was on the GBA Ambassador download. NES only got the 10 Ambassador games too, so more should be released.
I'd be the happiest person alive if Nintendo would just make these available, particularly Super Mario RPG: Legend of the Seven Stars and the GBA remake of Super Mario World.
EarthBound/Mother1+2 and Mother 3.I mean..heck yes. It'd be great, as long as they don't put games that are specifically multiplayer in...I still can't believe they gave out Kirby & The Amazing Mirror. CPUs are no help.