Late to the game on this thread, but I solved the uneven pickup volumes by changing pickups to modern windings....In my particular setup. for the Jazz configuration, I have Lollar Jazz 70's sounding pickups, for the Precision sound I have Joe Barden's. Not that those are the gospel, any modern high impedance pickup combination of your choice would work.
I am now able to nicely balance the mismatched volumes of the original pickups described by previous posters with sets of closer matched higher impedance ("hotter") pickups.
I still have my split P configuration set lower than the J pair, but the sound is now far more even.
I use the active input on my Quilter bass block 800, and with modest gain and fairly low master wattage I get a very even volume whether in J mode, both mode, or P mode only on active or active boost. I do agree with a prior poster that the P sound is more mid-range in tone, but still pretty growly to me.
(I don't think a recording studio would consider it an acceptable P bass clone.)
But the sound is fine for my rock cover band and my true passion is jazz, and the jazz sounds I get are amazing!
It is hard to contest the playability and comfort of the downsized body, fast neck and medium scale. I think anyone could make this their main axe with the right "modern" pickups of their choice. I don't know why the original Fender winding just don't seem to cut it. I did retain them for resale but it would be hard to extract this bass out of my hands due to it's comfort, versatility, tonal range and coolness factor!!!
Whenever I get g.a.s. I just have to ask myself, " What can the new bass do better than what the Urge does now???
I like light gauge strings, and typically use SIT in 40-100 range, however I have found nylon tapewounds sound and feel even better on this bass. I've tried LaBella and D'addorio. I would love to find lower tension tapewounds than 45-105, let me know if you know of any!!!