I realise this must have been said 100 times in this thread already and it must be getting tiring to hear, but Python is a terrible choice. First of all because who knows Python (lots of people do, but still only a fraction of programmers, whereas nearly all understand C/C++ for instance) and then because as a user you have to jump through many hoops to get the thing running, kinda gets in the way of adoption. It goes without saying but if I'd made and distributed my main program this way well I would have had to get a real job by now.
Anyway, I also have something almost constructive to say: Can we translate this thing into C/C++ using the assistance of something like Cython/PyPy/Nuitka/shed skin? If so I'd be willing to help (and I'm sure more non-Python developers would like to do that too), right now I'm working on making vector games out of my 2D/3D vector engine, but I'd love to contribute to working on GG2 in C or C++. If not then screw you guys I'm going home and I'll make a half vector half pixel art (maybe even half 3D, you could turn maps 3D by turning floor/wall pixels into extruded cubes and leaving the rest of the background maps on a 'wall') ripoff of GG2 as soon as I can figure out how to read map PNGs (I know how to load regular PNGs with libpng but how the heck do you get the wallmask and the entities out of the PNG file? Honestly I have no idea how this is stored and after googling it I couldn't find anything about it).