The brackets are now x0-x4 and x5 to x9.
So 70th, with exp off is the weakest character in their entire bracket for all battlegrounds.

The choice is:
- 59th with no Classic raid gear.
- 69th with no BC raid gear.
- 79th with no WotLK raid gear.
- 84th with no Cataclysm raid gear.

Or:
- 64th with greens and maybe a couple BC blues.
- 74th with some WotLK leveling gear and a few blues.
- 84th with 80k health, give or take but no new raid/pvp gear.

Raid Gear also equals PvP gear of that level.

Could still be a lot of fun.
But a level 74 in her bracket, will also have the same gear from 70 raids/pvp.
Plus anything they gained 71st-74th.
Plus more talents/spells/health/mana.