Well, my latest build is a chambered body and I'm thrilled to the tits with it. Your description of yourself sounds a lot like me. I too grew up on healthy doses of Metallica, Pantera, etc... but since turning the corner of 40 I've slowed down a bit and am enjoying a new life of the blues and/or blues rock. Same as you I've always liked that kind of music but it wasn't my style. I was skeptical about the chambered bodies myself but have to admit that I really really like it. It's really warm sounding. It also sounds great without an amp, damn near acoustic. Not to mention that it's really really light weight.
As for your "hard tail" conundrum, well, if a body is set for a hard tail I'm pretty sure they'll route it out for a trem for you. I didn't experience anything with what you're looking at but both of my bodies originally were top routed in the SSS configuration. I requested HSH and they did them up no problem, and at no extra charge. Now, if that holds true with a bridge route, I honestly couldn't tell you, but it's something to at least look into.
And, since you're moving into your blues phase, I think the chambered body might be something that you'd want to take a look at.
Hope this helps,
MULLY