Well it looks like it's in a DS box not a gameboy advance one. You said you were looking for th feel but not a actual one so you may want to make the box thicker

Well, that's partially the point, to update them to a DS box, not DS game. The old style DS boxes had slots where a GBA game could go, so really you could store them in one, as I've done with mine.

GBA boxes were cardboard, the old DS cases are plastic and have a spot to hold GBA games as well, so a couple of people prefer those

I knew that they had them I've been playing since red and blue X3 I got some of my cousins old ones

I can't see much on the back but you said you just wanted to make the cases look more up to date. Everything looks good and is in the right place. However if you are just updating the case, you might want to remove the thing about how the online interactions are not rated by the ESRB. Other then that all is good and want to print them out on the same paper they use for the DS and put them in DS cases just to see peoples reaction.