I guess I’m one of those anal types. When I install 3-way and 4-way switches, I always reverse the travelers on the opposite end so I can stage the room with the lights off and all switches in the down position. I like to connect Skylark and similar style 3-way dimmers with the little horizontal toggle switches on them so that I can stage them all with the left sides depressed when off, like on the single-pole dimmers.
If I don’t do it, it feels like the job is incomplete, just like if I don’t level the wall plates and set all the plate screw so the slots are vertical. If the plate screws are Phillips head, then I like the slots to be set level so they look like a cross and all devices must protrude the same depth through the plates.
Another thing I can’t stand is when the bulb socket height in recessed lights are not adjusted when the trims are installed, so that the bulbs all protrude the same amount.
To me, little details like this just make the job more professional overall. Many customers expect these things to be done and really do notice if they are not.