All I'm hoping for is that they spend the episode interacting so that we can get a better feel for their chemistry. Flute Spell didn't really show that, Jake being there and the quest kind of made it so that Finn and HW couldn't have the banter I would have liked to see. All we really know about them is that Finn thinks HW is cool and she taught him some ascetic tips and HW really likes Finn's hair and thinks he's an exceptional beast.
I'd be happy if more would be done to show how their chemistry is, even if they don't get together. Just want more of a foundation to build on.
Also I'm still impressed by how Finn killing Fern was handled. Sad because I'm sure they're just gonna do what they did after Finn Sword died, with Finn ending in a real fucked state but then the next episode has him acting totally fine. I hope they eventually get back and cover that stuff.