Nice one !

Well I suppose that all the fillets from the tread details generate tons of geometry. I would suggest to fillet them at the end of your project, otherewise you will have some huge trouble to duplicate the wheels inside MoI :)

I was on the same boat few months ago, trying to fillet every single edges, but it's a no way to go actually. I don't know what will be you rendering engine, but for example in max, lightware and maya, there are some cool shaders that creates micro fillets at the rendering.