Absence of end-game content : the downfall of every MMO.

[Malamasala]

Something worth doing perhaps?

I have the perfect idea for you.

Level caps, with requirement "real life full moon". So when you get to 20, you have to wait until there is a full moon in real life. Else you can't progress.

As you can see this fulfills all your demands. It is lengthy, maybe months. It is worth doing, because else you are stuck at level 20. And it is FUN, because you get to look for the moon every night and see the beautiful stars.

I honestly don't understand why nobody has made these MMOs yet. They sound super awesome.