I worked with piezos and active systems in my basses back in the 1990's. Not extensively, but with some of the best systems available at that time. But I gave up on the active systems because, in my experience, they just didn't have the dynamic range of a good passive system. And the style of basses I build are all about that old-school percussive attack curve. So, all the basses I've built in the last 20 years are passive. But part of the reason is the particular sound that I'm building for.
In my opinion the problem isn't so much with the electronics of the preamp. Good quality preamps do have good dynamic range. The problem is that the pickups that are usually made for and matched up with active systems are made weaker. Because the preamp is designed to be able to control the output level, frequency curve, and impedance to the amp, pickups are made with internal design that has less dynamic range in exchange for some other characteristic. A particular shape frequency curve, smaller envelope, whatever. It's okay, the preamp takes care of it and becomes a crutch to boost a weak design pickup.
A pickup that has a strong output level and dynamic range while wired passive, will usually sound just fine through a good quality preamp with the controls set flat. So then, why do you need the preamp? Just to have an on-board 3-band EQ?
What I'm saying is that most of the complaints about the lack of dynamic range with active systems, are really with the pickups, not the preamp.
Pickups designed to play passive have to work harder.
