I have no issues or things I'd like to change on any of my favourite basses.
My Lull PJ5 has no flaws and, apart from the fact that it isn't a 3 tone sunburst finish, neither has my Lakland 55-94D.
Precision basses were designed that way because in 1957 players played differently and the amps they used produced an entirely different sound. Most bass amps at that time produced mid frequencies rather than bass, so bass players needed all the help they could get.
Then after years of phenomenal success why would you want to change anything on the best selling and most acclaimed bass instrument on the planet?
Fender didn't remove the headstock strap button or tug bar for decades and they were pretty much redundant after about 1952!