This is a cool game. You really did a good job with the initial levels, and I was able to enjoy the game right away.
I think this concept has potential, but I think you should look into adding some more"juiciness" to the game. If the orbs snap together fast, or if the screen shakes when the two orbs touch each other, then it will really make the game feel immersive.
I recommend you checkout this game: https://itch.io/jam/gmtk-2021/rate/1079034 it has a similar mechanic, and does a great job with the "juiciness".
In any case, nice work!