Fun mechanics! Moving around quickly and smoothly. One strategy I found, I liked building up trash pieces to big amounts as backups if I couldn't plug up a 1m or 2m black hole or find enough pieces to plug it up in time. I'd suggest moving the Black Hole Collapse Timer to the left / near the Hyperspace Requirement increment. That way, I'd only have to look in one spot to have both information. I had been ready to plug a 8m hole with a 10m pile, but then I lost on time.
Other things I noticed: Jumping on the platforms was a bit wonky. couldn't always get up the next step easily. Had to step back a bit and focus on jumping, which lost me some time.
Also, it's not super intuitive that when you are holding a yellow junk pile, you can't combine objects to it. I was able to pull objects towards me, but it would not stick to the pile.
*Possibly, you could color it red as you try to pull to indicate that it cannot be combined? Or, make it so it does combine.
In the beginning rounds, 1-10, it felt a bit easy as I was able to easily plug up 1m black holes. So I spent my time collecting trash to build up multiple yellow hyperspace piles. However, I did notice the difficulty later as it the blackholes were increasing faster.
Maybe new levels / some better movement / different types of black holes / key objects may make a hyperspace behave differently?
Really fun game! I really enjoyed it!