What are you going to use the most (switch, control). Where are your hands when flying (control stick, throttle, prop, mixture, occasionally avionics/radio/nav)
Make a full sized poster board mock-up... draw or cut and paste your panel and switches on it... prop it up, sit in a chair and go through "flow" pre start, start, taxi, t/o, climb, cruise, descent, approach, landing, taxi, shutdown.... Spend some time behind the panel mock-up just sitting there (even in living room watching tV). Make changes.... (of course as you mention steal (borrow) ideas from internet....
You have to give some consideration of how you will wire and route controls for ease of construction and maintenance, even if it will not be optimal "human factors" or ergonomics.
For example I will have PTT only on my control stick, that is it (no need for it to be overflowing with switches). My RV-4 had flaps, trim and PTT on stick. It was handy must say, but had to be careful of inadvertent activation... However for wiring I am putting the flap and trim near the throttle for current project. I can always wire later, but simplicity and ease of maintenance is more important consideration for me....