Very fast moving gameplay and i say that as it seems like it take forever to rotate the planet sometimes like it takes too long to do the actions i want to do, it feels very polished and the endless nature of the game makes it feel somewhat lacking, the game's controls being varied gave me some confusing with the ground defence being activated with space and the air defense being left click.
i can somewhat see the theme in this game although not too sure of its presentation as i think you're intention was the leaving behind was the leaving the planet behind although i could be wrong.
The game however in the end of the day is very well polished with a very simple tutorial, however i would wish for a more interactive one or a simple overview of the controlls as there is a bit too many slides. Greatwork tho as the game seems very well designed and there is a few systems i can see that are working under the hood.