For the photo process, there could probably be multiple vectors, drag onto page, browse, open camera, etc... The API should be made in such a way that other frontends could be built, like native apps or an interface directly in Unity.
For the different types of level, I'm more worried about the representation rather than the game genre. Right now it only knows about lines, which can be used to describe a system of walls, floors or outlines. It'd be nice to be able to tag the polygons in between the lines through colour-coding (here is lava, for instance). A tile-based representation could be cool too (need to drop by the shop and buy some felt-tip pens to test this)