Hey man, I did my full 10-minute review during my Twitch Stream last night (twitch.tv/aaknox), but I'm going to summarize what I said during my review:
Art: Everything was drawn great. But the almost-one tone color of everything is red, so all those details are lost because of that. I would definitely suggest that you choose different color for the walls to stand out better.
Animations and Controls: Controls were very simple, which is I love. However, the animations need some revision. If the player starts in idle, then it should be a still frame instead of a mid-stride frame. The pickup UI looks neat though.
Sounds and Music: The sounds are awesome, guys! No complaints there.
Overall gameplay: The base concept for the game works for the theme. However, the level design is formatted for like a mobile game instead of a web browser game. Overall, once you guys find a great balance curve for the game, this will be a very good game.
Hope this review helps your team grow!