I like the concept, but I feel like you need to enhance the enemy AI and change balance a little, I felt there was no reason to not pick attack damage any time it pops up. Also, because the lines are what damages the enemies, you need to constantly observe if your line is hitting them, instead of looking what is being fired at you or what's on the floor.
I felt a little overwhelmed by all of this, but I'd like to see this game evolve! Good work :)