Walls absolutely need a much bigger degree of customization-specifically in direction and placement. I would absolutely LOVE to invent a design that no one else has, that absolutely rises above all else in terms of strategic placement. I would LOVE to completely own someone who didn't set up their walls well.
At that, having the option to use a preset or your own design would be AMAZING. I know you can place attachments to your walls, but I want to MAKE my own design... If that was a feature, it would increase my love of the game even further.