It's one of my favorite games ever so having this type of insight into it was very interesting. I broke apart the game being one of the ones i played the most in my life and there were still new information for me to find out (mostly explanations of concepts I felt but didn't know were there).
Also finally a proper answer for why the lack of circle pad compatibility, and it's unfortunate due to how the touch controls polarized the public opinion of the game (even for people who played it) and made it inaccessible to some.
I don't think adding the compatibility would be a sea of roses, as the video shows how intrinsically the game was designed around the touch screen aiming, and the entire control system design would have to change to make a smooth experience with a stick, and that was what I thought was the original reasoning for not including (at least paired with how close to the release was the Circle Pad pro made).
But I didn't know the circle pad pro added a burden on the system and that explains it a lot with how well the game runs while looking that good. Literally the only 3DS game where I felt the experience was truly taken to another level with the 3d effect on and I couldn't ever play the game without it.
Also explains why some games only supported C-Stick on the new 3DS but not the accessory on the other models
Anyways you should give Kid Icarus Uprising a shot if you haven't, it's a banger game