Quote from SerpenthTL;DR - Time will tell people. If the game isn't for you fine, if you want a refund cause you can't play single player offline fine. The community is not letting the game develop. Did you know about Mephesto runs day 1? Did you know about Baal runs day 3? Did you know all the sweet farming spots as soon as you picked up the game? Give it time people, we won't know for a few months whether or not Blizzard really dropped the ball or not.
I agree that time is the only true test of a game's quality, you run from one shiny game to the next and then you miss out on what's really going on. I say find a game you like at the beginning and stick with it to the end, one thing that the internet has provided is the ability to update games on an on going bases.