1) A new PvP only realm.
Why? I think you should make a PvP only realm that gives you rating rewards so the PvP players are more motivated to play, there haven't been any rewards yet for good players reaching high rating mostly because 80% of them were PvE gear abusers or bug abusers.
2)Which rating rewards?
Stuff that you can unlock at a certain rating. For example 2k: Brutal gear (s4), 2,3k = some cool heroic raid set, 2,5k = some tabard, 2,7k = some mount, 2,8k = challenge mode gear, 3k = legendaries that you can transmogg. Stuff like that so you can get motivated to compete in the 2v2 and 3v3 bracket. The 3s bracket on the FUN realm for example is literally dead beacuse most of the people dont bother to que beacuse it doesnt give you any rewards and not all people are experienced in 3s since they're harder than 2s.
3) NO rewards this season OR a rating reset.
90% of the players on the ladders right now are abusers and didn't get rating in any fair way. There's probably not even one person on the ladder that used full PvP gear before the pve gear fix.
For example: PvE geared locks could let you rot to dots by themself in less than 15 seconds, or mages that abused spellsteal glyph or the rune bug + mage food which gave you more than 20% health per tick so that you could get topped in just a few seconds, or rogues that abused shadow blades bugg etc. There's many more buggs that have been abused for rating.