My guess is that the "bright clarity" is not as much due to the purpleheart neck laminates, as it is to the always-on 8 dB Q boost. Add a Q switch, and you can turn off that boost. Make it a 0/3/6 dB switch, and you have more refined options - though if you need to cut through dense sounding guitars, a 0/6/9 dB switch might be more useful.
Having two filters lets you add some warmth here and a bit of sparkle there; then for bass boost you favour the neck pickup, etc.etc. I really like having two filters.
And wide aperture pickups.
And loads of mahogany in the wood recipe.
So if I were in your shoes, and sufficient funds, I'd add 3-way Q switch to the Essence, and order a bass with the wood recipe of the zebrawood Essence, Fatboys and either Signature or Anniversary electronics, with the quick tone switches.
Yeah, good points. My first Essence (an all-maple 6) had a q-switch. In fact my original thinking was that I would simply add either a q-switch or, more likely, add a q-switch and East-meets-West electronics to this bass. In fact, I am also still toying with that idea, although I don't know how feasible that is. Being a small-bodied Essence, it would likely need to be routed to accommodate the additional pots. So by the time I've paid to modify and refinish my current Essence bass, I am probably near the neighborhood (money-wise) of the deposit to start a new build.
The reason I am interested in East-meets-West, is that I had an Orion 5-string. Between it and my Series I, I think I had all my sonic needs covered. If I had one bass that had both tone circuits, and was a 5-string, I think I'd be all set.
Application-wise, I think for Grateful-Dead style stuff I play I'd rely on the filter mostly, and maybe thicken a touch with the EMW bass boost. For blues, I'd rely more on the EMW controls and have the q-switch in the 0db position. But it would be nice to have both options in a single instrument.