Need some advice for Les Paul rejuvenation

Caught a bolt of lightning

Hello,

I need some advice before I take my guitar into the shop blindly. I have a 96 Les Paul Classic and it doesnt sound like it used to.
Tone is flat and not very clear. I replaced a pickup a few years back but it still doesn't have a great sound to it anymore. (all my other guitars (teles and 335) sound way better, clearer and fuller I dont think that should be the case.
Any ideas what i can do to give it a kick start???
I am hoping to get a bigger sound out of it (Neil Young)
Any advice would be greatly appreciated!!!!!

All Those Yesterdays

How does the nut look on it? Almost sounds like you need a new nut.

Caught a bolt of lightning

Didn't even think of that, thanks man.
What are the signs that it should be replaced.
The more I think of it your probably right, all the other electric guitars I have/had when you play them "unplugged" they are resonant, this one not at all

All Those Yesterdays

are the strings fretting out anywhere?

in the end the natural sustain of the note is a combination between the nut the saddle and the wood itself.

Do you have a really good Luthier near you? And I don't mean a music store like Guitar Store (All though I'm sure there is some guitar centers that have a really good guy that works there).

If you had a Luthier you could take it to and get his opinion that would be your best bet. I have to drive almost two hours to get to a good one. But it's worth it...