Thanks for the honest feedback, its really appreciated. And the video is great too, super helpful.
It is hard make a game that is fun for both advanced gamers like yourself and the general audience. The approach I'm trying to do is Nintendo's newer approach with games like Mario Odyssey -- make a game that is very easy for beginners and casual gamers, then add in extra optional challenges for advanced players. That's what the space rocks and other paths are supposed to test, advanced execution of mechanics.
You are right that the gameplay is 1 dimensional -- at the moment, you can just move left and right and interact with things. I think this is OK for the first level, as you don't want to overwhelm the player with mechanics. The fact that you breezed through it is a good sign, as advanced gamers breeze through sonic 1-1 and mario 1-1 and get challenged in later levels. Future levels are planned to use a spring item & a rocket booster item to add more verticality and complexity. I'm choosing to drip-feed in these things slowly, saving for later levels as the player gets used to it.
Balance and rotational inertia are fun for trials/happy wheels type games. I guess I'm aiming for a simpler game and trying to straddle that awkward balance of a platformer and a racing game. Going for more of a Tony Hawk style. I will definitely decrease the air time to rotate though, I think you're right on.
Again, thanks for the feedback. I have a lot to reflect upon and improve upon before next DD, cheers.