Well, what sort of tone are you after? Based on your profile, I could see a wide range of cabs meeting your needs. Also, mention your budget, if you have no objections.
What do you want to accomplish? What are your reasons for needing the gear you have/want?
Without knowing any of that, I'd say grab the Ampeg SVT210AV cabinet. Small 2x10 cab that will work for many sits for relatively small outlay of cash, and you can add a second cab and cover 90% of gigs... The only thing missing from this cab (same as the massive SVT810) would be the "sub" frequencies, which are mostly annoying, and generally don't fit on stages or recordings anyway.
Good point as far as recording, etc. If you want to get loud live with your B2r, turn the eq level (not the eq itself, the slider off to the right) up all the way and re-adjust your pre/master volumes. Keep in mind this is making up for a flaw but it sounds pretty good when you do it. It is not comparable to an amp that doesn't have flaws to make up for. Another Ampeg " damn I wish I would've" moment. Except for the B15 (the greatest amp ever produced) and the SVT (the most popular, but by far not the greatest amp ever produced) Ampegs generally suck and must be "made up for". Meaning all your knob turning is to make up for what's not there but should be instead of enhancing what's already there. Anyway, boost the eq level instead of the eq frequencies.
Cab ideas? 
