there's tons of BA's out there! you just have to do some looking around. off the top of my head, Liquidzgrl has some BA's posted in a thread in the LiQuID FroZen YoGurT section of Custom Roms; carlz28 has done some "non-traditional" ones; there's a paid app in the mkt (Absolute Systems) that has quite a few BA's to chose; you can do a google search for droid BA's; etc.
like i said, these are just off the top of my head. and, if you look in the individual custom rom sections, and even the individual themes sections, a lot of people have developed BA's for individual roms and themes.
there's enough out there that i'm confident you can find something to your liking. it's just a matter of doing some searching around and finding what you like.