Considering the les paul..
Classic Les Paul tone is a sum of its parts; scale length (it affects tone), construction (neck and headstock angle, single cutaway), mahogany AND maple. That maple top changes the tone, as does the thick slab of mahogany beneath it.
Many people think mahogany is dark, whereas it's actually not. A good specimen, I mean. It does have emphasized mids. Maple also has a lot of mids, buf different.
A good les paul is not muddy. I have a bright one :) A bad les paul is dull and nasal.
Upper fret access is not the best, I know. However, many manufacturers (like Feline) have improved that greatly. And even if you go the regular LP route, they have many different neck sizes. Although I myself don't mind the PRS wide fat at all, so maybe Gibbys have almost always bigger neck than you like :)
-Zaned