Re: Electrical planning
I'd suggest a rough layout in CAD and then match drilling the actual holes into whatever board you are using. We've used ABS and polycarb with success in the past.
Vertical electronics are handy for space saving, just be careful of some gyros that have to be mounted horizontally to function. Also would suggest taking the time to heat shrink connections, zip tie / fasten everything down nicely, and add labels—neat electronics look nice and are easy to troubleshoot.