I use 0603 exclusively in my drivers as I want to utilize the space as much as I can. I also bend pins on the MCU, put the MCU where the spring usually is (for space and easy access to flash the light without full disassemble) and cut of the tabs of the 7135s to make them shorter (custom Eagle library part). One of my drivers where I’ve done this: Mod: My take on the convoy S series with side switch mod.
I did a design with 0402 sized components but they where to annoyingly small for me to work with, so I’m sticking with 0603.
Btw, nice to see you back, if only for a while.