Choosing to put a 1 time paywall behind it is literally the best thing they could have done. Making it free 2 play would mean a consistent stream of hackers, and has a pretty fucking high chance of shitting up the community. Diablo 3 has a slightly higher paywall and it does fucking wonders for the game. There's a pretty significant amount of botters in Diablo 3 atm (including the majority of high ranked players) but that's more due to the fact that an autofarmer is harder to detect than something like an aim-bot would be, because Blizzard does big bans infrequently, and because botters only really affect you if you're one of the people pushing for a top 100 time in Greater Rifts. If a paywall makes it anything like Diablo III is then it's a good thing. Also means you're not gonna have to pay for characters, which looking at the pricing in HoTS means you'll save a lot of fucking money.