Well, let's give it another shot!
F2P (and I do mean F2P, not a free trial, no annoying restrictions)
Large playerbase,
MMORPG
Not grind orientated (but action is still a good thing)
I have played these
Forsaken World,
Perfect world,
Vindictus,
Rusty Hearts,
BOI,
WOI,
Dekaron,
SRO,
Hellgate,
Maple Story,
Everquest 2
Runes of Magic
Mythos,
Dragona,
Spiral Knights,
Drakensang,
MU (lol, oldschool),
Lineage 2,
Dungeons and Dragons,
Champions Online,
League of Legends (not MMO, but people tend to offer that one regardless)
Heroes of Newearth (same situation as LoL)
Alods online,
Archlord,
Requiem,
Metin 2,
Ace Online
Aika global,
Digimon masters online
(That's as much as I recall, please don't offer these games.)