Isn't the scoring a bit harsh? (and other things)

[Thundercracker]

let me preface with some background: in rhythm games i cut my teeth on the DDR series.

this game follows the DJ MAX style of rhythm game, yes? some parts are very difficult to adjust to. particularly the step-block fall speed. the default speed here seems almost equal to the speed of the steps in max300, the fastest DDR song. this speed does funny things to my eyes, and i cannot play for more than 3-4 songs per session.

the scoring system seems overly harsh:
https://steamcommunity.com/sharedfiles/filedetails/?id=3448988167
i did not actually miss any steps, and i still get a low D? that feels like it should be a C.

we start with only level 8 and 10 songs... why do we have to unlock the easier songs?

the UI could use some keyboard controls. like having WASD and the arrow keys change song and difficulty selection or using the keyboard to select from the "retry, song select, main menu" menu if you fail a stage.