I absolutely support giving league hosts the ability to separate promotion/relegation among tiers (allowing movement between Rookie and Pro and locking Elite until Pro is sufficiently populated). As it is now if you're in Elite it can be very difficult to find populated leagues except for a certain few, and only then if the schedule fits yours. As it is, I'm actually going to be shutting this account down in a couple of weeks (the second of my three) simply because I can't find a league that suits my preferences anymore and is populated.
I shut
my first team down in October when I couldn't find a league that suited me, and now I'm facing the same issue with this team. At least I'm still enjoying racing with my third team and it doesn't look like that's going to change any time soon.