Weirdly I've only played vanilla survival but this genuinely sounds precisely like my experience. First we built a zombie farm. Which gave us some weapons and xp. Then a chicken farm, for food. Then a spider farm. Then we found an underwater temple. Guardian farm time! Oooh, and an ender pearl/xp farm, iron farm, gold farm etc etc etc.

We spent days and days in game automating away as much resource gathering as we could. Until the server was basically finished - there really were no more farms to build.

So we started a new one :)