I don’t think solo queue and team rank should be separated. All games works this way and aoe2 has a small community split across regional servers so basically your idea is impacting wait time more than solving the core problem.
But I agree with you on the fact that we favorite a map and we don’t get it. I myself solo queue a lot favoring arabia map in 2v2,3v3,4v4 (all checked) then I get Arena or Hideout which is the opposite of what i want to play so I just alt f4 and queue again.
So yes we need to improve favorite map system as I explained in this post to prevent these inconveniences.