Thank you all for your answers, gives me something to think about! No need for apologies, info helps, although you can imagine; I've asked this question elsewhere online and at times hit a awl with people saying: 500K for humbuckers.
I don't fancy the sound of a bright humbucker in a maple strat with 500k, that could be very bright. I don't want a twangy humbucker tone.
I want to get a bit of G-type sound in the bridge. I also didn't want to go down the 'hot' route unless I had to. I know that output will equal more 'fatness' but I don't want to overpower the neck and middle. Also, I play through a Blackstar, so there's enough gain there; I personally don't need output. I prefer lower output humbuckers.
I also didn't want to put a 500k vol in where, say the bridge tone is located because then I'd have no bridge tone and I'm not up for adding another 500k tone.
I've also read that the Mule doesn't suit a strat, can anyone dial in here?