I'm with you on the "keep it simple" front, but is the one extra syllable of "Newbury West" going to break the bank?Just "Newbury" is fine, let's not overthink it. This is where the GL intersects Newbury, people will figure it out. If you're so concerned, see "Boylston" station.
The issue here is that the relationship between GL and Newbury is essentially parallel the entire way, until they subtly swap sides. At least at Boylston, it takes a sharp turn...at Arlington it intersects perpendicularly...same deal with OL at Mass Ave.
Yes people will "figure it out"...but is helping them at essentially zero cost such a shame?