Avoiding Oblivion gates was deceptively difficult. You try to wlk around one, and you practically run into another. Especially if you were up in the mountains, it was very difficult to get around them and not go off course.
Dragons will be far less frequent, you can avoid them without running into others, you can run from them, other people (guards) can attack them for a distraction, and they can fly away on their own if they don't want to bother with you.
Yep, in some places, it was an OB gate-fest, so after a few characters, I just ceased to activate the main quest...
As for dragons, I remember Todd Howard saying he once ended up chases by three of them, which caused them to decrease their appearance. So, maybe you're right (I hope so).