Thank you for the feedback, PZ!
You can actually also push enemies back to give you more time! :) Flower pushes away anything that is blue!
In the later waves, there are some bullet patterns that actually require that you defend them properly, otherwise Miss Flame will not have a path she can go through! I tried to only make the player NEED the block a little bit later so that it wouldn't become too overwhelming for someone not used to shoot 'em ups! (Also on a later wave there are enemies with pink shields, that require a bullet to be reflected onto them first!)