Whilst the ability to commission in branch as a crewman has temporarily ceased, I believe starting it back up again once the nav branch naturally dies in years to come will benefit the career stream for high calibre rear crew whilst assisting the RAF fill many of the SO3/2 jobs left behind.
As for it always being the 2 wing master race making the key decisions I'm sure that will always be the case at the highest level and rightfully too, however at station level I'm sure the COS at Benson would disagree!
Unfortunately the RAF don't seem to want to develope 'leaders' there seems to be far too much emphasis on 'management' for my me.