OK, I think I have completed the dialing in of this Matsika Alembic. To make it more "useable" on gigs where noise can be an issue, I changed the caps on the tone pots to .01 from the original .0033/.0066, and it has maintained good top end clarity while taming the sizzle created by poorly wired clubs. I also experimented with a variety of strings, and I found the Ernie Ball 40-100 flat wound cobalt strings to be an excellent compliment to this bass. I always like lighter strings, and these are very responsive and even. I can't get the single LED to work, mainly because I think it was for 9v, and just burned out with 18V. My guess is he added it when he cut the power wires for the original fingerboard LEDs, hoping it would light up since he did not use LEDs in his replacement neck.
The look and feel of this bass are stellar. The tone is powerful and full with lots of variation. It is a chunk when it comes to weight, but I have played it both seated and standing, and it is not much of an issue. It has the typical reach issues of all long scale "point" basses. Nothing that ruins the experience for me, but you know you are not playing a Europa or Rouge. All in all, I am more than pleased with the bass, and even though trading an original refin 1958 Fender Precision bass for it does not make sense financially, I know I will use this bass much more. It's just more "me".
I recorded with it on a track I wrote during Covid lockdown where I originally used the 1958 P. I wanted to compare the tone between the two basses. As always, the Alembic tone is the better one.
It has been a journey this last week, but the outcome is very satisfying.