Thanks for playing!
I thought of the theme as limiting the player in these small levels. You would have to think about where to place which tower, but in the end i left it for the player, if he wanted to plaster the level with lasers, or create own challenges like only placeing one tower per wave or sth..
But i agree, the theme isnt very obvious.
I am thinking about uploading another version considering all the feedback, thanks for that! :D