[quote name='goldblaze' timestamp='1342580744' post='4960311']
2D game engine with 3D things in it
Cannot agree more with Ashaman73 about feature creep. One year seems a bit long maybe you can set yourself shorter intermediate goals like interactive demo in 3 months, pre-alpha in 6, etc..
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You either never worked in a team before, or you had a very consistent designer that knew what he wanted and didn't want to add anything on top what you already had.
Anyway. I guess it also depends on what you exactly want to achieve, with what tools, mechanics and all the micmac that comes when making a game. Does your programmer know anything about game programming (I'm assuming not, else you wouldn't ask it here).
Creating the effect of going in depth in a 2D engine might be a problem if you don't know how, in that regard perhaps a 3D engine would be better. But if you want to keep things simple, a 2D engine would probably do the trick.