Wow, rpgcubed, thank you a lot for your review and compliments! Those ideas are really good hints! I really want to try adding more levels / or changing the level over time after the rating period.
Its quiet hard, game design wise, to come up with asymmetric leveldesign ideas while maintaining the mirrored concept. as soon as I introduced obstacles you change the "axis" of the player/enemy and you can simply win by e.g. walking backwards into a wall to make the enemy fall of the circle :D
I also implemented a push back on hit, which was a really cool feel but obviously resulted in the same issues :D
So I guess changing the level that influences the projectiles but not the movement is the way to go(?) e.g. magic glowy walls that change location / roate around the circles ....
Thanks again for your amazing review!