I think this is awesome! I love the simple yet challenging puzzles. I think the ability swapping is a really interesting and fun feature. The tutorial levels are a great introduction to the game. The puzzles are well thought out. The last puzzle took me a minute to figure out and was rewarding when I finally did.
The only issue I noticed was the camera. Like someone else said, I thought the aiming felt a little sluggish. At first I thought it was just me (I'm mostly a console player, so not used to aiming with mouse). There were also 2 incidents where the camera kind of freaked out. The first time was in the 3rd puzzle (I believe), where you hit the button and sprint through the door. As I got to the door, the screen made a complete 180 degree turn. The 2nd time happened randomly, where the camera went ballistic (only for about a second).
Lastly, I think including the purpose of the blank ability things in the tutorial levels would be good (it's entirely possible that I just missed it..). I really struggled with the last puzzle until I accidentally put the high jump ability in the blank ability thing. I realize these were placed in previous levels, but I simply ran through them and straight to the goal so I never noticed my current ability getting placed in it. I thought it just deleted my ability and I wasn't really sure why. However, it's not something that made the game any less fun and actually added to the difficulty of the last puzzle (therefore, more rewarding once realizing what I needed to do to make it work).
I really look forward to seeing more of this, great job!