What genre this game would be?
From the video i think it's some "space invaders" like game.
If it's not i'd like to know the genre, other than that try to considerate the option to turn your ship in the direction when you are turning, to increase the game feeling, right now it seems a bit unreal. ( Always if it isn't meant to do that in the first place)
About the triangle number instead i can't say much, I am a beginner on unity.