I just have Zelda of these so this is a good deal for me, lots to choose from. I think I would go with Pokemon X and Bravely Default, since I think these games have less potential to drop in price than the others. I also want Mario Golf, but since it is $5-10 less than everything else, it isn't the best value of the bunch.
If I wanted to get 4 games I'd probably have to do separate orders...
Actually, most of these games have very little potential to drop. Maybe Bravely Default-- in the DS generation, Square games tended to stay in print and drop down to the sub $20 range. But the 1st party stuff....not likely. Any of the DS Kirby games, Mario Party, etc. all stayed pretty much near initial MSRP. The only 1st party games that went below $20 were heavily marketed games (which I presume had larger print runs) like Rhythm Heaven and Brain Age, and 1st party published, non-character RPG's like Glory of Heracles, Golden Sun, and DQ9.
So I'd take advantage of this deal. In fact, I am! Say hi if you see me at Best Buy, I'll be the one carrying a stack of 6 3DS games (Pokemon X, Mario Party, Mario Golf, Zelda, Yoshi, Kirby)