Great job on the demo! You hit the mark exactly. It feels like Super Metroid, but with it's own style and mechanics. I'll be looking forward to the full release!
I did encounter a bug I wanted to report. I use a dualshock 4 controller on my PC and it incorrectly detected some of the buttons.
I have them mapped like this: Square is attack, Triangle is secondary attack, X is Jump, and Circle is Secondary Weapon Swap. However, this is how the game detected that configuration:
If you need any more info from me just let me know. Great job and I'm looking forward to seeing more!