I doubt they'll do that. Look what happened to the 50 & 60 roulettes once SB hit - the policy seems to be merging roulettes when possible, not create new ones.
That said, I'm all in favor if the lower-end roulettes would also count for the tank mount achievements. Not only will there be more ways to get points for that that don't necessarily involve 61+ dungeons, but SB only has the 5 dungeons and that gets old after a while.