Well Code of Princess is kind of like Dragon's Crown, a brawler with RPG leveling and better gear, extra characters, and an enjoyable enough story but you have to like that or it's boring as sin. I don't like Lords of Shadow as the 3D franchise goes, but the 3DS game basically is a hybrid of Castlevania 3 NES and God of War (energy/magic bar enhancement and button combos for nasty hits) which I found hard to put down until I finished it. I know that RE Mercs wasn't the best, a lame demo turned into a game and one with a really evil save setup where you can never reset the data which sucks. I mostly was just listing third party stuff I tried out before or was aware of. It's why I never listed Monster Hunter which is huge as I never could get into the slow plodding pace of it on the PSP when I had it before.
I think the deal is these days is Nintendo has the third party support still totally on the handheld front, but the difference is that you're getting quality over quantity. With the GBA and DS you got a heap of games, a good bit more, but there was so much filler garbage. I'm not saying 3DS is empty of it, but there's far less shovelware turds or mediocre third party releases from more reputable companies.