BB92 looks pretty versatile. Enduro makes a BB92 - BB30 adapter. Not sure how good it is, but might want to give it a look. http://www.enduroforkseals.com/id258.html
Enduro makes decent bearings, but I've found that the grease they use isn't very water resistant, and your bottle sweat will eventually destroy them. Your best bet is to remove the seal, flush out the bearing with a cleaner, then repack it with a better waterproof grease (I have been using marine grease, available at any fishing or trailer supply store). This applies to both the standard steel and ceramic bearings.
In terms of cranks, you'll be looking at any Shimano offering or a SRAM GXP crank, unless you use an adapter.