What endgame content is there?

[FlameSword]

I finished the main quest a while ago and I can't help but notice that this game has, well... an active playerbase. I felt like the main quest was frankly kind of short and lackluster. So, what do you all spend your time doing? What am I missing out on? What cool content is there that I haven't seen?

[Swissski]

There is the main quest which can quickly be completed.

But there are also the secondary quests, all the objects to collect, get all Steam achievements...

[Schtroumpf]

A lot of secondary quest, some even hidden(the man who puts apples on people), some cool hidden/creepy places to find(only 2/3 in fact)
Exploration, getting better stuff (exp weapons + all 5c components), killing stuff, farming to get reapers, having fun online if you find the good people
And there is not only one main quest, but several in between the differents regions.

[Swissski]

Yes, many things in the game are hidden like some missions. I just discovered the Apple and the tree one... For now I'm trying to find all the collectibles.

The content of the game is immense in reality.

[big knee]

if you havent killed a reaper yet that's always something fun