Felt bit too "sluggish" for me, few suggestions:
1) Instead "press once to activate minimal dash", I would prefer having dash meter allowing to keep key down for continuos dash, slowly decreasing until you can no longer dash. Meter could be recharged by coins or another new item.
2) Possible add flying/jumping enemies, while most of the enemies are easily killed you would have to time your jump/dash to avoid those flying/jumping enemies.
3) Maybe different music for menus and levels? Same soundtrack all the time can be bit too much to listen.
In the end, game was fun to play even if its "early draft".