Since we have simulated projectiles, wall height is pretty important. As of now, only grenadiers, air, and artillery can bypass a wall. However, anything can hit a tower if aiming directly at it, as the tower is far taller than the wall it's shooting behind. Towers are usually squishy enough that they can be taken down in a few shots, so you only need a few grenadiers to take down a laser tower anyway. I've noticed that, after a fight, the only things remaining are the walls. They're supposed to be the first things destroyed, as they should be blocking incoming fire, but they aren't. I can't imagine there being much to prevent this, but, if walls were made higher and/or we got new wall types, that would help quite a bit. Perhaps a wall that's twice as expensive as a regular wall, has 1/4 the hitpoints, and is tall enough to block air units from flying over it. It'd prevent bombers from rushing to the anti-unit towers, but only if the opponent bothered to place the high walls in strategic positions. Simply making an entire wall out of high-walls would make it vulnerable to ground armies. Alternatively, a wall that "hovers" over a small area and blocks aircraft like peregrines from firing at other air units. It could also slightly protect from orbital fire, but not by much. Just a thought. It might be wiser to just make everything else shorter in comparison.
No one will take the time to put up walls when they can easily counter with AA, or fly fighters over the base.
Directional turrets (ones that dont rotate) could act as air walls. They would essentially be short range AA. If Air is outside, its hard to get in your base, but if youre inside the base already, its not going to do anything (the short range makes it useless for non-wall AA. Maybe it only shoots up)
