Might wanna talk to the creator of the orginal addon. They made a change to hunters rattings overall. So the ladder wouldn't just be hunters. Was really nice as it's made people not want to play/verse a brain dead class
The only way PvP will prevail at this bracket is by community made wargames for both bgs and arenas. Wouldn't be the first time a bracket has had to do this, prob won't be last.
20 is always a safe option. Always a community for it. Whether it be PvP, or PvE focused. Plus I'm sure there's still some 20s wargames going, or some in the works. At the end of the day the choice is yours, so have at her.