I would go with rosewood, as well, for the fretboard, and mahogany, koa or alder for the body. J99A pickups are on the bright side, so you might consider the H50A pickups, as well. I would remember, though, that it's always easier to warm up a slightly bright sounding bass than it is to try to brighten up a bass that lacks the upper end you might want at times.
How versatile would you consider the j99a's? I've heard really good things about them which is why I wanted to try them out. I generally go for a darker tone but my bass that I have now does that decently well and I wouldn't mind having some variety

