Hi again. Well, different strokes and all that. I've played nothing but P basses for several years and have found that I get the best results by playing to its strength, which is the low mids. The P bass's low mids let it punch into and sit in any mix perfectly. To enhance this I prefer nickel rounds or sometimes nickel flats with a somewhat hot pickup. I like the DiMarzio Model P but there are many options. My favorite P bass is my 80's G&L SB - 1, which has a very high output, and very mid - present yet very clear and smooth sound. Our guitarist tonight thought I must have a bridge pickup, the notes are that focused and defined . When I showed him it was a straight - up P he was surprised. I like it so much I've bought another G&L MFD pickup for one of my other P's.
As has been said , P basses generally just 'work.' But there are exceptions - cheap imported pickups may not have enough wire on them which will make them thin and bright sounding. They may also have weak magnets, contributing to low output. Even some otherwise high quality USA Standard P basses from around 2006 to 2010? (somebody help me here) have iffy pickups, lacking in mid punch causing you to get lost in a live mix(but they can work really well in the studio). All of this is easily fixed. Whatever your issue is you'll find it. It's not rocket surgery. : D