While interesting and new at first, all RR has done is limit choice and customization. Every champ has their optimal build/keystone. Old runes at least allowed small, but differential, customization on top of the masteries. Now it feels we just have masteries.
I've found myself much more bored with league in pre season. My friends list has dropped dramatically; talking to them I don't think I'm alone in feeling this way.
After 4 years of league, I think I might be done.