Amazing demo, I enjoyed it a lot. I can see a lot of work has gone into this, and enjoy the animations and overall gameplay feels great.
One thing I did notice I was consistently doing, which might be a me problem, is forgetting to pick up old friend magnet at the start... especially in the hub level for some reason. I feel like it would be helpful if the magnet spawned in front of the player and called out to be picked up a little more. I almost imagine a little voice saying "hey don't forget your ol pal Nate!" (does the little helper have a name?) ... I appreciate its not always in reach every level from the start, so some kind of call out might also help draw the player's attention over to it, as it really feels like your friend and you feel almost naked without it.
I can't wait to play more of it, thanks for sharing and the fantastic video series!
-Chips