A bunch of beginner CNC router questions

I'm working on designing and building my first CNC router. As I am not a mechanical engineer nor have I much experience with building (apart from K'nex and Legos from my childhood), I have virtually no clue what I'm doing. That said, I do know how to use a CAD program, so I've been working over the past two weeks to make what I think will be a working design.

Now that I have completed a first draft of my CAD model, I have a number of questions:

1. I plan on using 3/16" thick 3003...

A bunch of beginner CNC router questions