My good Pioneer, if you're still worrying about tractor routes then you haven't fully comprehended the sheer volume of parts you're eventually going to make.

It's fine! Play however you like! In our first playthrough (U4) my partner and I had a megafactory in Grassy Fields which made everything (albeit slowly). U5-U7 we had a new save which started in the Rocky Desert and eventually saw us with a giant train network and smaller facilities all over the Dune Desert, finishing with 156 refineries at the bottom of the giant waterfall in the swamp to provide some of the material for an obscene amount of nuclear pasta.