What can I say about screw drivers? I have a Craftsman Ratcheting Magnetic for most jobs, a Short 3/8 flat blade for opening cowling and a Craftsman Ratcheting Off Set for hard to reach places. The largest selection I have that diversifies it all, is a Bag of Bits and Bit Holders that I can connect to any of the ratcheting handles to give me access to virtually any place. This Bag contains various lengths and styles of bits as well as 1/4 inch square drive adapters for male and female to hex. This combination keeps my weight down and my tool bag uncluttered.
I also carry a precision screwdriver kit as well for electronic potentiometers and relays.