I'm a little bit confused by the premise here. The idea of a hack and slash and a runner sounds alright, but one of the biggest, most important parts to nail down of a runner is a sense of speed and momentum; even without any upgrades, the game should feel like you're constantly moving forwards, like you're, well, running.
Except here, sword slashes plant you on your feet and stop you in your tracks. The idea of attacks feeling weighty and heavy sounds like a good idea for something with weighty sword combat but for a runner it really doesn't work. All momentum stops, and the feeling of running infinitely to the right simply doesn't really work.
Now sound-wise I'm a little saddened by the complete lack of any real soundscape, but you're a small team and y'all don't really have a sound engineer.
But what really does work, and what makes me wonder if this game couldn't work in another form, is the spritework. The characters look great and the animations are full of life and personality. I think this would work as, say, a more traditional platformer or heck, a weightier 2D action game, as long as you were willing to put in the time to really polish the hitsparks. There's potential here for a great game somewhere. It's just not in this current form.