Hey, sorry for the late reply, haven’t logged on in a long time.
Typically we have 250k for single coil and 500k for h/b. Do it the other way around and the singles become harsh and the h/b becomes muddy,
Some folks use 500k volume pots on a HSS but then use 500k or 470k resistors which are wired to kick in when the single coils are selected, this makes them more like 250k pot which is really what you’d want for single coils. See the photo below...
Regarding caps, it’s 100% personal preference IMO, depending on how muddy, middy or clear you want it when you turn the tone down.