The B Wing was intended to replace the Y Wing in the rebel forces. Supply, maintenance and in-flight problems meant it didn't quite work out like that.
In game terms, IMO, a B Wing should be somewhere in between an X Wing and a Y Wing, and I think it is. I think part of the problem is that the B Wing has a barrel roll which neither of the other ships do, and another part of the problem is that the gap between the X Wing and the Y Wing is quite narrow. Slotting the B Wing in there had the side effect of overshadowing the X Wing. And part of the problem with THAT was that the X Wing really needs a little something else to make it more distinct from the other two.
Personally, I think the X Wing needs 4 red dice. Yes, 4. And that makes it 5 at close range. Given the limitations on it's dial, and it's generally brittle nature I think that's fine. It would also make it distinct from the B Wing in that one is durable, but doesn't pack a lot of punch while the other is powerful, but not very durable or maneuverable.
This would open up a larger slot between the X Wing and the Y Wing and allow the B Wing to slip in there nicely without overshadowing the X.
Thoughts?