As for the style, don't worry about it too much either. I suggest doing whatever comes naturally, because usually you get enough helpful feedback on these forums to get the model where it needs to be without completely overhauling it. Obviously we try to stick as close to the original artwork as we can, but because we are building out of nothing but cubes you have the liberty of some degree of artistic freedom. Basically, it's your interpretation of the original artwork. The models in this mod range greatly in their level of complexity, but the models that get approved are (ideally) the polished ones that have clearly had a lot of effort put into them.
So just be thoughtful in whatever approach you take, model in whatever style makes you happy, and make sure you put effort into each model.