The new Everquest game looks promising if the stuff about the non-linear questing and destructible environments isn't just the usual nextgen hype. We'll see.
I'd love to have got to grips with Eve but I just couldn't get my head around the wider PvP game which of course is where all the real action is to be had. I've kept toying with the idea of trying to get back into it, but the learning curve feels really daunting.
SWTOR is doing pretty well post F2P. The population has stabilized and seems pretty well balanced between subscribers and F2P'ers. They polished it up a lot since launch, especially endgame raiding, streamlined the levelling process, added plenty of new content and some much needed 'quality of life' features. It'll never shrug off some of its fundamental design flaws, but there's still no MMO that can rival the story-telling and companion system.
I'm not sure how well SWTOR plays as a pure F2P, there's a lot of restrictions. But as an ex-subscriber you get "Preferred" status anyway which gives a few extra perks and is certainly enough to level up and enjoy the story (but not suitable for endgame stuff). What some players seem to do is subscribe for a month and buy some unlocks with in-game credits (to unlock things like purple gear, extra inventory space, extra quick bars etc) and then revert to Preferred. I'm mostly active on Rep side these days, but still have my Imps so if you want to do some Imp Side levelling, give me a shout and I can kit you out with some decent gear (assuming you have at least Preferred status and can trade).