There's honestly nothing I could say about this mod's quality that hasn't been said before. It's quite possibly one of the best and most polished mods on the whole MB. Anyone reading this probably already knows this, and considering how long it's been since the last update, I don't think anything will change about it until STJr finally makes good on the promise to remove P_TeleportMove.
However, I do have a few gripes. For one, I don't like Mario's acceleration. Luigi is fine - in fact, his main, defining difference from Mario is what makes him exempt from the issue I have. Mario's acceleration, particularly the start of it, is way too touchy. It makes platforming far more difficult than it needs to be by making small adjustments practically impossible. He takes off at a full sprint at the slightest touch of a movement key. Maybe this is less of an issue when using a joystick, but with digital movement, he can feel ironically a lot harder to control than his slippery-shoed brother.
That feeling of touchiness is not at all helped by the presence of the side flip. I'll often be trying to slow down to avoid falling off of a platform, only to go rocketing off of the opposite side because I accidentally jumped while skidding. I don't think I ever activated it on purpose, other than to test for its existence.
Also, this might just be a me problem, but I tend to get the Spin and Attack inputs mixed up a lot. I often end up plummeting into the abyss when I'm trying to launch myself to safety, or throw myself at mach 10 into the wall and/or horizon when I'm just trying to stop myself in the air and land on a platform below me. Doesn't help that, even when I do get my inputs straight, my Mario Odyssey reflexes often screw me over, as I try and use the Jump key out of a ground pound to start a dive.