i don't know of any transparent pickups. active pickups
are can be better; by decreasing the inductance, the resonant peak is attenuated and extended in frequency. (the voltage output is much lower, though, so the pickup needs its own internal preamp.) however, even fairly "even" pickups aren't exactly transparent.
the only truly transparent part of the signal chain is the power amp. i think the cabinet may be even more colored than the bass. (if you've heard A/B tests among basses, it's not that it's hard to differentiate them, but it's remarkable how subtle the differences are between basses.) the point of a preamp is to color the signal.
so maybe it's a little optimistic to make your claim hinge on the pickups. i would also point out that when you're dealing with room acoustics, you're dealing with phase as much as frequency. suddenly the phase response of the EQ matters. there are sevearl different active filter topologies. so even if you have adequate adjustment (e.g. 1/3 octave for the really surgical stuff, quasi- or fully-parametric for that one problem area), the phase response matters when you're making a bunch of adjustments.
good luck trying to figure that out during soundcheck. do you know the topology of your EQ? do you have another unit that uses a different one?

I only have one tool so I have to make it work at every job.
this. but i usually don't have problems hearing myself and making myself heard. maybe my cirrus is magic.
robb.