The difficulty doesn't make the game enjoyable for younger players at certain areas.
Jet Force Gemini is just.. unexplainable. Its just such an awesome game that its just different from most other shooting games of its kind. You can play as a guy, a girl, or an err.. dog XD. That's fun though, because you start off as playing as one of them and as you advance the story mode, then you can reach and unlock tons and tons of different things. Other games of its kind aren't really like it, since it offers lots of things that those same other games don't quite have.
I would almost call this a masterpiece, or even go as far as to calling it that in the first place, because I really fell in love with this. The weapons and the enemies that you have to fight make it violent, but then again not so violent, so its even fun to play for little kids, although they're not really supposed to play it.
There is nothing to hate about this game since its just so great, and it provides tons and tons of tons of things to do, which can really be fun. I really would say get it now, because even though it's a shooting game, its more of an adventure/shooting game, since its really versatile. I would say definitely get this now.