I know exactly what you mean. I like the grittier high-end sound as well. Your best options would be another MusicMan, a Status, Warwick Corvette $$, or a Yamaha TRB series bass. These all have a lot of treble available in the sweeter frequencies.
Some actives do sound very harsh in a nasty sense when you give the treble some serious boost due to differing frequencies used on the preamps. All the basses listed above sound quite sweet in this situation, but the nasty harsh treble category [for me] consists of active Fenders, Spector Euros, Jackson CMG's, Yamaha BB's & Ibanezes.
That isn't to say I don't like any of the above basses - It's just my own personal experience. Hope this helps
Rich.