See I think masteries and runes are stupid, they have an impact in games that have nothing to do with playing ability or skill.
And the gameplay is a little bit simpler. No denies, no courier, more ability spamming, etc.....Also the summoner spells same thing...it makes it less about playing skill and more about what you happened to bring with you versus what they happened to have....idk I still have fun playing it, but I definitely look forward more to Dota 2.