I think you can do much better than the B100. I suggest you hit up your local guitar store - or better yet, take a road trip out to a Guitar Center and play as much gear as possible. Find something you like, tell us about it, and if we tell you it's decent; look for it on craigslist.org You can save so much money by going used and get better quality gear at a lower price.
The GK combo amps are excellent and far exceed the majority of bass combos out there.
Gallien-Krueger MB210 2x10 500W Ultralight Bass Combo Amp: Shop Bass & Other Musical Instruments | Musician's Friend
If you can find that used, I would grab it in a heart beat. Otherwise, I suggest you find a separate cabinet and head. Cheap combo amps are great for low volume practices/low volume gigs. Playing metal with a guitarist is going to require some decent firepower and if you throw a drummer in the mix, your Acoustic B100 is not going to cut it.
Don't worry about versatility of bass rigs, any rig out there can work for nearly every genre. It just depends what kind of tone you are going for.