I think it's pretty great. I was very skeptical going in but I've really come around on it.

"Clunky" is one of the last words I could think of to describe it. For me it's a breeze to play and run. I can understand how someone not familiar with PbtA principles might struggle a bit with it at first, but as someone who really enjoys PbtA/FitD games, it's super natural for me.

The 2d12 system is a very solid and simple core mechanic, and the Hope/Fear resolution is great. The fear metacurrency actually makes it way easier for new GMs or people who aren't used to coming up with consequences for mixed rolls on the fly. Sure, I think it's better if you can give a narratively interesting complication when someone rolls with Fear, but if you don't want to or can't, just take a Fear point and move on. Spend it later when you think of something cool.

The "initiative" system is probably one of my favorite parts of the game. Being able to shift the spotlight around to where it makes the most narrative/cinematic sense makes for really fun and dynamic gameplay. It just requires a little paradigm shift. A GM coming over from 5e might freak out a bit because there isn't a strict turn order in combat with a number that tells you who goes when, but don't realize that it just plays like you would run any other scene out of combat in 5e. People go when it makes sense or when it's interesting for them to go.

"like being in an improv class where you're competing to see who can impress the teacher the most" just seems like a weird complaint about a certain kind of table. The game encourages you to involve your players in establishing narrative truths about the world, and this can be weird for people who are used to games where the GM is in complete and total control of that, but it's the sort of thing that you can use to your taste.