Until reading this i'd never given the physical aspects of puckups size, shape, or placement any thought. I settled on jazz basses a long time ago and while i do tend to use the edge of the neck pickup as a thumb rest, i also move from between the bridge and bridge pup up to just above the butt end of the neck, playing over the fingerboard. If there's a thumb anchor where i'm playing i might use it but the neck pup is pretty much home base for my thumb. I move forward and lighten my touch or backward and dig in, but pup size, shape, or placement has never been something i've noticed, even when i was doing the revolving door bass audition in search of what i thought was the best playing bass. What i learned in the aftermath of that search that it was not the bass holding me back.