Watching you play was actually interesting, really sorry we had you rage so much :(
The game actually does have mid-air course control. Air movement works just like grounded movement, albiet a bit slower. The only thing you've no control over is your vertical speed, this one is constant according to your current madness level.
I think our core problem was more about difficulty curve and teaching the player detailed mechanics and control over their character, rather than sheer character controller issues. Not saying there aren't some of these too though!
I've made a full run here: https://www.youtube.com/watch?v=5Zq7fqZPZV8
Thank you for playing though, and thank you for your honest feedback!