I can say, having finally played enough to burn out / quit, that Farm RPG is pretty much the ideal idle game for me. It is simple, pleasant, non-predatory, and strikes the perfect balance of encouraging habitual play without making you feel bad for not playing it. There's a huge amount of content, the game changes a meaningful and interesting amount over the course of your playthrough, and it rewards creativity & pathing without really requiring you to bust out a spreadsheet.

If there's any flaw in it (besides a meaningful dearth of social aspects, which in my case could almost be argued as a boon), it's that the endgame is toilsome. My last six months of playing Farm RPG were all the same: log in in the morning, spend five minutes doing my daily chores, make a bit of monotone progress on whatever the current milestone was (which was always rote), and then log out. It's hard to hold this against the game specifically because all idle-games seem to struggle with this prolonged endgame — but it's worth calling out nonetheless.

★★★★