It can be made very small if so desired :
Although I’m not sure what host to use it in, it seems like lot of side switch 14500 lights have the switch mounted on the board, which isn’t very problematic, just need a different layout, some have 2 PCBs like the Sofirn SP10S, that’s a bit more annoying, plus the SP10S is too big for a 14500 light in my opinion.
I’m interested if you know of small 14500 hosts that would be suitable.
There is the FWAA, adapting to it is easy (just add a switch ring), although I prefer a single emitter version, which apparently is in the work.
I wish Hank would make a small 14500 light, and a small 18650 single emitter one too.