I mean, how long you got? almost all of my ideas are photography based so like...

a simple one is that I'd like something that exists at the intersection of Dead Rising, Fatal Frame, and a 6DOF shooter. trapped in a place, you're reporting on it, but also the easiest way to deal with enemies is the flash on your camera sending them scurrying off. the flash leads to worse photos though so you're kinda balancing the whole situation out

the next one I'd like is the one I'm working on periodically, where it's basically Qix mixed with a traditional Touhou game. instead of shots, you're trying to enclose enemies and the (mid)boss in lines so that you can take pictures of them. the more enclosed an enemy or boss is, the more damage you do to them. you can also enclose bullets which will clear them from the screen and contribute to your health. also, if the boss touches the enclosing lines before you fully enclose them, the lines break and you take damage

I understand that this really doesn't line up perfectly with the concept of the spell card system, but I'm more interested in making the game fun and interesting first