I love Archie! Fantastic character design overall. A lot of what I noticed are probably things the team is already aware of.
There are some slight snags in player state transition that kind of results in awkward feeling behavior. I felt like at times jumps did not register right and the wall jump would switch between sticking and falling in a way that felt un-intuitive. That said, the moment to moment movement felt very good and the animations really sell it. Archie looks so happy to be jumping around.
Near the end of my time, I also discovered I have some sort of air dash move, that unless I missed something I don't remember being told about or unlocking. I felt kind of lost towards the end. After the battle arena the leader of the arena kind of gave me a quest, but I could not discover any additional areas to do that quest.
Last little thing is a graphical one. There are some areas where there are large background set pieces, which are very blurry and kind of distract from the overall unified aesthetic. It would probably be good if those images were imported at a higher resolution.
I love the characters and the world and would love to see more!
edit: I just saw someone mention a final boss so now it's very clear I missed something somewhere.
Also, the concept of one whole exercise is very relatable.