Here are a few suggestions. I know there are more I've not thought of.
Have you been through Jethimadh Tower?
Have you done all the races?
Have you been to all the subway stops?
Have you visited all the streets?
Have you collected all the cubimals?
Have you raced cubimals?
Have you unlocked all the seam streets?
Have you been to the new party rooms?
How many badges are you missing?
Have you adopted a newbie?
Have you fought the Rook?
Have you collected everything from the ancestral lands?
Have you joined a group (or groups)?
Have you started a group?
Nothing. There's no point to the game. Quests are the closest thing it has to an objective.
This "game" reminds me of PSP's WTF: Work Time Fun where you basically do mundane real-life stuff but on a screen with pixels! Nihilist gaming FTW. WTF
Bludwaggie has an excellent list of non-quest goals. There are plenty of others that can be added to that, as well, including ones no one else has thought of before because you were the first creative person to come up with it!
Also, if you are sitting there waiting for a long skill to finish learning so you have something new to do, I recommend spending that time figuring out how to maximize your skill learning speed by donating to giants and spending the favor. That's been keeping me very busy lately.... Also, you could collect 11 emblems from each giant to turn it into an icon. That will keep you even busier.
I suggest you join the Greeter team - At launch, we were short of greeters by so much that only about 10% of greetees got greeted. Care to help? It's a very busy job, but also very rewarding!
Chemisie, they must not have that problem these days...I've signed up to be an official greeter weeks ago through a bug report and haven't heard back :(