The game is in a state of constant beta testing. Patches come weekly, a blessing and a curse, as old bugs are fixed, new ones are introduced. It's clear the developer, Gazillion, has very little internal quality control. Server crashes and downtime are frequent. New heroes are added monthly, but they simply recombine already existing skills.
PvP has been in public "beta" for 10 months and yet is still a very poor MOBA clone. Oddly, the game has an MMO style raid, but it feels quite of place in an ARPG title and can't complete with the raids in a true MMORPG.
The official forums have an extreme amount of moderation. Posts regarding game breaking bugs or negative feedback are quickly deleted. I found myself reading numerous forum threads that disappeared after navigating. This results in the forums having a "Pollyannaish" feel as only the most positive and pleasant posts survive.
Sadly, I recommend you stay clear of this product. Though it doesn't have the Marvel license, Path of Exile is an excellent free-to-play ARPG that remains my top pick in the genre. Diablo 3 and Torchlight 2 are also very good. And Grim Dawn, from the creators of Titan Quest, promises to be amazing and is already far more stable and playable than Marvel Heroes 2015.