Go look at an old farmall or ford tractor and understand how they solved these problems 70+ years ago. Be careful thinking you are smarter than those engineers.
I appreciate all your points about the sort of tractor best suited to your unique circumstances. I don't see anything about our communities designs which prevent you from constructing such a machine using our parts and techniques. I think it'd be a neat design to have among all the others which can be built this way!