Replacing WoW with a free MMO will not help, assuming you're trying to focus more on what some people call "real life". You'll just need to exercise more control over yourself for that...
Otherwise, I've played a bunch of free and semi-free MMOs and found most of them shit. Runes of Magic was an okay WoW clone with some interesting gameplay choices, but rather grindy and way more boring then WoW when it came to it. And if you thought that WoW story was pretty shit and the quests were badly written, wait till you see Runes of Magic... In most cases, it shows all the things you SHOULDN'T attempt when trying to engage at least somewhat intelligent people in a fantasy story.
Of course, given that it's an MMO, people don't read quests anyways so they don't care.
Overall, it's the same grind but with slightly different graphics and gameplay. Meh.
Although open world free-for-all ganking is pretty cool. And you get random drops on player kills, some of their gear or some of the stuff in their inventory or nothing at all.
Except if you kill too many people, guards in cities will start coming for you.
And of course, high level gankers will be on your ass in more popular zones. All rogues, invisible and able to instant kill ya.
And I have to say it again... the story in that game is so atrocious, I can't even express it with words alone.
Dungeons and Dragons online is also an obvious choice, although frankly I'm tired of it. I played it a bit when it was still P2P and I tried it again a few months ago only to quit forever last week. It's rather boring and repetitive... The game itself is great, for sure, but real D&D is so much more fun compared to it.