Kid Icarus Uprising is the best online game the 3DS can provide. If you're looking for a social/talky game I'm not sure if you should try Heroes Of Ruin. It should be really cheap at this point and I heard its the only game that has a mic and you can chat online.
3DS FC:4425-1580-1611. MPH expert of the Kid Icarus Uprising boards 3DS chat: http://xat.com/mph93 SKYPE: xIvan321_