I dont own a 305 but I have a feeling you're gonna get a lot of "it depends" replies.
Almost like asking what strings people use on their 305s.
VERY subjective.
Different heights will give different results and depending what you personally are after...it depends lol.
What is the problem you are trying to remedy? Are they sounding weak? Lack of sustain? Sound too thin? Too boomy?
Depending on what it is that you are wanting or wanting to change...that will "deecide" what you need to change heightwise.
So...let us know what it is that you're having problems with and what it is that you want..or want more of..or just why it is that you want to adjust the height.
AND...pickup and pole height DO make a difference. It's probably one of those things that guitarists usually overlook. They dont make pup height adjustable, nor do they put threaded and slotted (or hex or philips) heads on the poles just for fun or because they like to waste money.
YES...pup and pole height are quite important and should be set to where you like them best...BUT...we still need to know what it is you're after before we can recommend height adjustments and which way to adjust.
TGIF!!!