Well, Phrecia was pretty fun.

It was better than most "real" leagues. Here's why:

Things were pretty massively shaken up.
Self explanatory. The new ascends and the idols changed everything, and they happened to actually be fun.

Player power remains high.
It doesn't take forever to start chaining t16 alch and go maps.

Borrowed power is explicitly borrowed power.
We don't expect the OP stuff to go core so we can just have fun with it without worrying about the base game being ruined in the long term.



PoE's rough spots the last 5 years or so came from damn near everything going core in some fashion and then the nerf hammer having to come out in force. It's better when leagues are more experimental and the players and devs don't feel locked into the new content existing forever. Harvest was the most obvious example of this: horribly OP, no one really expected it to go core, it did for some reason, and everyone came out feeling burned and annoyed by the whole thing.

We don't expect idols to come to the main game and enabling us to get 10x the reward from content we already do. But for one league, it's fun.