Congrats on your first release!
You've got a solid progression and a sense of encounter setups. The platforming bits work well, too.
Take note of places where the player is equipped to engage enemies in unfair ways (ways you did not intend, usually where the enemy has no clear way of retaliating or returning fire effectively). There were two specific spots where I remember cheesing the enemies, one was an Ogre behind bars, and the other was against the Vores in the last room. The last room was a pretty good setup, but the Vores had minimal room to move and not enough distance to launch many projectiles before I was able to overwhelm them with grenades, using crates as cover.
Check how your doors appear from both sides, when open and closed. The door into the final room caused z-fighting, due to having one of its faces in the same space as the walls of that room. There are other little things like this... you may be able to see me looking at such things in the demo below. These are small issues, though, and should be easy to spot as you continue mapping.
Congrats again on your first release!
Demo of my run (normal difficulty):