I agree with running cims and mini cims 1:1.
As far as chain/belt for the cims, I would suggest using 3mm pitch GT2 profile timing belt. This is what we used this past year and I know some other teams did as well. Just make sure that there is enough rap around on all the pulleys.
looking at the miter gears, you'll need to make sure they're very well supported and have thrust bearings in place to deal with the thrust loads. We've used the needle thrust bearings from mcmaster the past two years with success.
I like it so far, but there's always room to make it smaller, simpler, and better
