Great game, it was a lot of fun, so here are some tips:
Show the player the controls! When I played the game, I didn't realize that there were actually weapons, I just assumed that the gun did the damage. Only when I looked into your description did I see that you had to switch to attack. Most people don't really want to exit out of the game just to find out about the buttons that you need to press, instead just quickly put together a tutorial or a quick picture showing the functions of the 3 tools.
Just make the portal instantly tp you to the next room when you touch it, that way the player doesn't have to find out that they had to press E
The party members should just automatically follow you once you recruit them, regardless of whether or not they are in your line of sight, I constantly had to backtrack to get the dwarves just to follow me because they got stuck