EffClef,
The Series bass less controls: I've been thinking about something similar myself. The audiophile's mantra is the fewer components in the signal path, the purer the tone. With the right woods in a bass, I'd settle for one great tone directly to my rig [Glock BAC plus ART SGX Nightbass SE effects box].
Like you, I've been thinking Alembic pickups to preamp to cable, but I'd want something more generic than the five-pin--perhaps 2 balanced 1/4s or 2 XLRs. That way I could upgrade to a better cable [or at least a different one]. With the low crystaline OF audiophile cables available today, running a high quality broad band signal to the rig should be a piece of cake. Once there, all sorts of things could shape the tone.
The other possibility would be a variation on the Line 6 Variax. Only in this case, add a midi cable from the bass to the tone shaping unit, with only the midi controls themselves [say volume and sound selector] on the bass: analogue signal, digital controls. I know this means a dedicated external box, but haven't the Series basses always required that for the best tone?
What do you think?