Must haves:

Kid Icarus
Luigi's Mansion
Fire Emblem Awakening
Both Zelda 3D ports

Also
Bravely Default / Second
Hyrule Warriors Legends


Plus DQVII & DQVIII remakes are coming this year, definitely get those.

Shin Megami Tensei IV
Majora's Mask 3D

People here have already named some of the best known games. Get them. If you're a huge RPG fan, try and go after just about anything put out by Atlus or Xseed. There's too much to name. You'll have to look the up, but most of those games that especially have the Atlus logo on them are worth getting. Also, don't forget that you now have access to a whole library or DS games as well. There are plenty of games to get for that as well.

I recommend the pokemon games. Even though many write them off as kiddy games, the truth is they are really great RPG's. You always feel like you went in quite the journey at the end.

Definitly get all the ace attorney stuff you can get. If you havent played the trilogy you got that. Otherwise dual destinies is really gripping for a novel like game. New one coming out soon aswell.

I will alert you to this sugestion. Sorry to say tiffac, but i went through bad times with that game.

Project X zone is a game that is cool for 15 hours until you get tired of the repeating animations. Then you realised you have another 35 hours to go. Its EXTREMELY boring and it overstays it's welcome by ALOT. The story is patheticly bad, so don't expect it to get your atention. So, don't go for this or the sequal unless you have a high tolerance to repetitiveness.

Heck mercenaries 2 is better if you want a strategy RPG fix. At least it doesn't overstay it's welcome by much. Fire emblem is the only way to go on this sub-genre on the 3DS.

It was a really good game.

fe fates, zelda albw ,xenoblade,shantae

Are you suggesting that I was derailing the conversation with my direct reply to your attack of "this thing" lol? It's fine to not like a system, but if you bring a discussion off track, don't try the defense of how the discussion is going off track, like I said your post had nothing to do with 3ds games, even in terms of Nintendo handhelds it was mostly regarding how there would be a successor to the 3ds and not the Vita. At least my comparison included the console in question in this thread, yours did not.

Also what does Sony not developing games for the Vita have to do with the 3ds or games recommendation for it? or... just want to try to get a cheap dig in but then point out how this should be a 3ds thread? I see. I'll drop out of this back and forth though just felt the need to point out that I was just responding to derailment, not doing it.

It is a very different beast to what is on the consoles, I played a ton of it on the X360 and that is a fantastic game as well, the 3ds version is a different beast entirely but is great in its own way, other than the DS Sonic games like Sonic rush I think Generations is one of the best Sonic Titles in the last decade.

I'm not sure of your console history btw, but if you missed out on the DS then I would say to check out

http://www.metacritic.com/game/ds/sonic-rush

and

http://www.metacritic.com/game/ds/sonic-rush-adventure

for some classic 2d Sonic on the go, really those were great too but I thought the 3ds generations was a better game personally.... even though it reviewed slightly less well, but I think that was just a lot of reviewers gave it grief for not being a port of the (at the time) HD twins version of Sonic Generations if you get me?

Edit - Seems to be rather cheap online, can't see US postage but guessing it would be less than I'm seeing from the EU http://www.ebay.com/itm/Sonic-Generations-RE-SEALED-COMPLETE-Nintendo-3DS-3-DS-2-2DS-GAME-/371611494615?hash=item5685c568d7:m:mDXKrk1Y15VbUmyjuoSOSSQ

Luigi's Mansion and Zelda: A Link Between Worlds are essential purchases. Kingdom Hearts 3D is good if you've played previous ones (plays most similarly to Birth by Sleep or re:coded). Get Sonic Rush, Rush Adventure, and Colors, all of them great DS games. Mario & Luigi: Bowser's Inside Story is also DS and easily the best M&L game.

I responded to another PSV owner that in a 3DS games recomendation thread felt the need to demonstrate his disappreciation for the very system the topic is about. Things like "return the 3ds" and buy a PSV instead and how bad the 3DS is in a thread about 3DS software, just shows how much some really want attention for their system of choice, willfully ignoring how off topic and inflammatory they act. It´s very telling that you had absolutely no problems with this kind of bs, even worse you felt the need to elaborate on this nonsense. People shitposting in most 3DS threads and at the same time still to this day telling how superior the PSV is in unrelated threads, shouldn´t be surprised if they get served some reality check in regards to the actual situation of the PSV or about Nintendos and Sonys handheld business in the near future. Thanks to Sonys disinterest I can´t even say that it isn´t well deserved.