Addictive concept: easy to understand, but hard to master. I liked it! Definitely can see this developed further with multiple enemy and weapon types. You gotta be fast or you will be overwhelmed - and as you are not allowed to shoot multiple enemies at once, you basically have lost then. I'd maybe put the dash on a cooldown independent from kills, to reward skillful maneuvering a bit more. Rarely used it as it is now! Also I'd consider letting enemy ships bounce away from each other on collision. You could bet on this and hit them right after, when both ships are (hopefully) isolated, thus easy targets.
My game: https://njamster.itch.io/wonkey (playable in browser, not mobile friendly)