Diablo III was pretty disappointing when it arrived, but Blizzard were allowed plenty of time to fix it up into its current pleasant state because many clickfans found themselves distracted by Path of Exile [official site] anyway. Grinding Gear Games have continued to improve their free-to-play action-RPG all the while too, of course. Today (this very minute, if all goes to plan) they launch The Awakening, which they call "the biggest and most far-reaching expansion of the game to date". Sez you, sunshine.
The Awakening introduces Act IV of the story, complete with new areas, bosses, skills, and so much loot to beat out of monsters. Also, more stuff. Check the Awakening subsite for more. It is nice that it's touching up the game in general a lot too, rebalancing quest rewards, improving network syncing, and making lots of small "quality of life" UI improvements.
I had a crack at Path of Exile years ago, but found the sprawling skill tree off-putting rather than enticing. I felt more like I was presented with a large number of opportunities to waste skill points than the freedom to create the hero I wanted. That's a hazy memory, mind, from a grumpier time long ago. Tell me, what's it really like?