I haven't been overly particular about pups - they either sound good or bad to me. The sound I have liked the most over all these years was an old Gretsch Supertron bass pup. The guitar Supertron used several thin sections stuck together to make a blade, while the bass version was one big thick blade. It recorded wonderfully, and sounded fine live. I always attributed that to the blade design. It sounded really even all the way across, and was punchy low and high.
The laminated blade is used to give the pickup a brighter tone, since it inhibits the formation of eddy currents, which are small swirling electrical currents that form on conductive surfaces in the presence of a magnetic field. These current then produce their own magnetic field that opposes the main magnet's field, and that kills off some of the highs.
Bass pickups sound fine with a little eddy current loading, and it's often used on purpose to warm up the tone. The DiMarzio Model One has a thin brass plate on top of the bobbins for this reason. The old Gibson Firebird mini humbuckers had a small thin brass plate on top of the pickup under the treble strings to smooth them out a little.
My least favorite has been the DiMarzio p-bass with the allen screws. It is a hot pup, but has that grating overtone. But I believe the open top Allen screws were selected for the way they react to the strings vs a regular screw.
I used to think the allen screws were used on purpose because of the shape, but now I realize that it was just because they are rod shaped. The real reason why the Model P sounds that way is the pole screws are high carbon steel, and they use ceramic magnets. The winding is about the same as a real P bass. So the magnets and poles gives the pickup a harder tone.
