I have a lvl50 chamipon character AND a lvl14 alt also.
The lvl50 bracket is the very best thing which happaned the warzones since december. I enjoy now the warzones with both characters. My lvl50 is facing lvl50 characters: no lowbies in our group, etc. Expertise however an issue: in some occasions we have to face ppl with full Battlemaster gear, and this is annoying. And in some very rare occasions the enemy seems very weak: these are the ppl who are "fresh" lvl50s. In most times killing these folks are not a challange but simple buchering - and I'm a Jedi not a butcher.
So the two solutions:
1., Just drop expertise: there is no need for separate PvP gear. We have crafting skills, let the players to do good gear. PvP commendations could be exchanged for rare materials, etc.
2., Create separate brackets for Champions and Battlemasters and "fresh" lvl50 ppl.
Lvl10-49 bracket is good. OK, killing a ~lvl40 character is tricky with a lvl14 - but not hopeless like full Battlemasters. Usually I'm the lowest lvl in these warzones but most of the time I'm in the upper third of the leaderboard in DPS or number of kills. In lvl10-49 the game is about the player skills not the expertise and this is a very good thing. I definitely want this in lvl50 brackets also.