I've seen several pro musicians gig with Bronco's - some completely stock, so there is no worries there as its totally gig worthy as long as you don't abuse it. The stock pickup, despite being a single coil guitar pickup is clear sounding but not very full, which suits some musical styles. If you play with overdrive/fuzz/distortion than the stock pickup is ideal.
I had a Bronco where I replaced the stock tuners with a closed back set from an Affinity P bass (which was pretty much a direct replacement) they were more robust so I could put some high tension Fender flats on it. These strings (despite being full scale) brought the bass to life and sounded great, gave a more meaty and fuller sound.
The weakest point of Bronco's imho are the electrics. Replace them with some mini Alpha (linear) pots, and if you did want to upgrade the pickup, I would suggest a 50's style single coil like a SD SCPB-3, or if on a budget the Roswell VTN4 (those used on Harley Benton PB50s are really decent). Both of these would mean a little tweaking of the pickguard to fit, and it's not a difficult job, but the result will be massive over the stock pickup and electrics.
Many people have used Hotrail guitar pickups as a replacement, which are a direct replacement, which i found really filled out the sound (good), but lost all the clearity (bad).