My 2 points
- A $5 limit switch can go a long ways to protect a $6000 robot.
- KISS (Keep It Super Simple) is a good idea if it is your first time writing an autonomous mode program. For example, banner sensors are simple to use and program while IR or encoders tends to be more complex.
I setup a simple line following autonomous mode last year using 3 banner sensors. It was simple to build and program and when it was complete it was reliable. Now that experience has made me more prepared to write a much more ambitious encoder based autonomous mode this year.