Even if it's a Vita level of power, that would be fine for me. I think no matter, though, Western third parties are more interested in consoles and mobile, so I doubt they'll dedicate a lot of time and money to making games for whatever Nintendo's handheld is. Japanese third-parties on the other hand would be well suited to make content for the 3DS's successor, as the 3DS and Vita have been selling rather admirably in Japan, while the console market isn't doing so hot.