I agree that it's time for another arena. Several suggestions:
1. The obvious (and boring) choice is to simply create a second MA identical to the first. A waste of resources, IMO.
2. I wouldn't mind seeing a second MA with no night-time and slightly closer bases, perhaps with RPS added in the first MA (one MA could slightly more "realistic" than the other). Everyone would be happy with this outcome.
3. Or perhaps have one MA "europe"-style, with the other being "pacific" style? This worked well in AW, and IMO would work even better in AH.
4. An easy fix might be to modify the CT so it becomes popular, but this might involve turning it into nothing more than a "team-planeset" MA.
5. A FA-style "country-based planeset" arena might be interesting, but there'd have to be quite a few plane additions for it to be fair at all.
6. Perhaps a "mid-war" arena, with post-summer 1943 planes either perked or completely unavailable. Such arenas, however, have consistently proved unpopular in other sims.
Given a choice, I'd vote for either #2 or #3, or maybe #5 once the planeset could support it.
J_A_B