>>2307691Flame Princess arc was a good example of a romance subplot as written by people who have no idea how to handle romance subplots for a director who didn't want a romance subplot but was too bus focusing on his own other thing to veto. The less said about it and the way it ended, the better.
Having said that, I think Puhoy is probably one of my favorite episodes since its a better example of how Finn's later life should have gone. But picking an actual favorite episode is hard when you have things like The Limit and Dad's Dungeon and Dungeon Train. On the other hand, stuff that references AT's post-apocalyptic nature like Islands and Be More also appeal to me, as I just find the idea of modern and near-future weapons and vehicles existing alongside fantasy a-la Wizards captivating.