Feels great! I know you can remap, but I would add d-pad to the default map along with analog. The game seems to read the movement input as digital anyway, and dpad always feels faster to me in these games. Also add more contrast between foreground and background, for gameplay reasons.
The platforming and combat feel pretty cool, and I like how you can slash the bullets to break them. Heads up, I got stuck in a pit after falling in the area where bullets are shooting upward from below the screen. No game over or anything so I'm guessing it was a glitch.
Looks good so far!