Lately I've been playing a good bit of Zentia. It is a good game to play casually and pop in and out of as you feel like it, it's also great for keeping busy if you want something fun to distract you. The thing I like about Zentia is that there is so much to do. Constantly there are in-game events, dungeons, solo dungeons, casual leisure games and that is just what I've seen thus far at 23.
I think another aspect that keeps me engaged is taming mounts and pets, which is fun. This morning I logged in to see the hunt activity was going on. Basically it is an arena where you can tame a mount if it is up, you're flagged for PvP though. I was the only one, glad I didn't have to fight anyone, and a wolf mount was up. I was pretty happy to battle him then tame him, he is one of the mounts which you can use for combat as well as having a decent travel skill. Stuff like this is just fun to collect.
While the game appears to be cartoony and childlike quality, it really has depth and a lot to do. I'd advise anyone to check it out if you want a decently paced theme park with lots to do. There are even tradeskills, which I have yet to try.