Here is my top 5 list. Based on my opinion
1. Aika Online (2009) - 10/10
Definitely the best for me. I cant find any game with better mass pvp than this.
Good gameplay. Nice pvp and plot line and Awesome character skills and item crafting.
I dont know if the game still alive tho.
Sample video of Aika Online gameplay.
2. Dragon Nest (2010) - 8/10
It's a fun anime mmorpg and the only one with action based combat.
Unique pvp system. Good customization for character and gameplay
3. Eden Eternal (2010) - 8/10
Anime inspired game. It has cute graphics Still have many players in the game.
Fast leveling, 20+ playable classes and 5 races. Can switch between classes at will.
4. ArcheAge (2013) - 7/10
Its a fun game, good graphics and nice pvp system.
5. Blade & Soul (January 19, 2015) - 7/10
Still haven't played it yet. But base on YouTube videos I think its a good one.