I played through a few times, although I'm not sure my "techniques" made any difference - by the third time I was just clicking and holding until I won without any attempt at doing anything; I didn't even aim for the circles anymore.
The green circle only appeared for me each time during the tutorial and never again but later on I'm sure a couple of the reds were actually a deep orange so I don't know what that was about.
I really like the design of the icons on the sides, although I don't know what any of them are intended to mean since they aren't labelled. They're so good that I actually want to point people to them to say "That's how you design icons in a Unity game so it doesn't look like a Unity game" because people so often default to Unity's placeholder styles and fonts.
Considering that in real life I haven't even been able to conquer my neighbourhood block but here I was able to expand and take over the universe(?) multiple times, I think I can award the game 5 conquests out of 5.