More things you should add I guess
For the Swipe thing, on PC you should make it to (Hold this key and release it at right time or combo drop haha!!!) and still leave the swipe option for both in case somebody's a Osu! player
As you combo you should get a gauge, when you press a button it slows down time and allows you to get easy combos at the cost of said meter
Spin input, use arrow keys to UP RIGHT DOWN LEFT a certain number of times, causes a change in combo direction
And if you're getting the hang of coding, add a freestyle mode which allows you to pretty much fly around with a set moveset you can use to do cool combos and stuff
I am aware this may be too hard, but would be a treat to see