I did a raised saddle on my too-tight bass, and it had no effect on tightness. The Marvin wire tailpiece also did not help. We raised the tailpiece up a bit and that didn't do the trick either. I brought the bass to at least 4 renowned luthiers to no avail, although a new, little scooped, fingerboard did help playability, but not tightness... I tried all kinds of strings including Velvet and Spiro and Evah solos tuned down. Plain gut D and G did feel looser, but I didn't want to go that route. I gave up on the bass.
I loved my bass. But I finally gave up as well.