Drive by wire works great (Ram trucks, Toyota, Nissan) and it's certainly economical with space, but I would think you might want some redundancy so you're not stuck out in the frozen tundra some where. Cable, if you have the space, is pretty KISS and bullet proof.
Your set up looks great. Enjoy it. I've tried to stop fixating on my MPG. I am way better than I used to be. I love my truck. I love my camper. And the MPG? As the saying goes, it is what it is.
The fab work is amazing. I look forward to every installment. I can hardly wait to see it in action but then I'll miss the build so you'll have to start another project as soon as this one is finished