Do you think I need to state these relationships more explicitly?
I think players would forget if you made them use it in a tutorial. Maybe some more intuitive color coding would help? Having the purple enemy be countered by the white attack and vice versa doesn't make immediate sense.
What's your suggestion? More homogenized room shapes?
I think enemies could to handle corners better, rooms with a ton of cover are so easy because enemies get caught on each other and the terrain as the same time as they try to get to you. Fighting in rooms like that feels like the game is handing you a freebie.