I rarely PvP and haven't done arena in a while, so these changes mean little to me.

I am wondering though, with the fact that nearly all of the season 4 gear will require 1550 or better ratings, how this will affect the difficulty of climbing the rankings. There will be no reason for the people who putter along for a 1300 rating to play any arena once they buy their gloves and/or off-hand (the only items that don't have a requirement on PTR). Same for the people who either putter along for a sub-1550 rating or just aren't good enough to crack 1550+, I assume that they'll buy their one or two pieces and quit until next season.

Won't this make it tougher to get specific ranks? I'm going on the assumption that the arena brackets are zero-sum, so if all of the 1000-1500 players left, then the next tier will drop down and become the new 1000-1500 rated teams. Or is this incorrect?