I think many of us were expecting 694xx to head to BH for 265, but streetlite maxes are a good option as well. Not a typical end to end service you're right (I've done it twice, though purely for fun!!) and some friends did it when having a day out in Salisbury, but agree it's not intended that way. However regarding the 59 reg B7RLEs, their main downfall is their lack of windows, and echoing what others have just said I remember sitting towards the back on one of them on a warm day in rush hour traffic heading into Radstock (from Bath) when there were no doubt roadworks on as well. Not pleasant! And this looks likely to continue.
I think 377 is more of an end to end service, though it would seem few actually use it these days. In all my years of using 377, I only ever used it south of Street once. Does it not pick up a lot down that way?
For the record, the one time I did use it was late 2009. I found myself stuck in Wincanton of all places, so took the 58 to Yeovil, which back then was in the hands of 66960, then a 377 back to Wells with one of the brand new B7RLEs.