Right now, I'm leaning towards getting a BB1 for the neck and keeping the 57 classic plus in the bridge. I think I'll see how that works out. If I don't like the bridge after that, I can do some more swapping. I like what I'm hearing on clips of the BB1 in the neck position, I think that is what I'm looking for, some bite in the neck which is really lacking with a 57.
The Seth Lovers are intriguing as well, but are a little more expensive. I might try those if I'm not happy with the BB1.