[Sgt_Walrus]

Hi
My understand is that..

1. It varies. Sometimes one tree will block LOS, sometimes you can see through two or three.
Trees do not have "height". Look at the height read-out of the hex itself to know the height of a hex.

2. The AI has no advantage. It is just your perception that they see you more than you see them.
It is possible that you are being outplayed by the computer :-)
If you move too fast, you will see less. If your units are inexperienced, they will see less. If the enemy is experienced, he will hide well and see you earlier.
There are many parameters to seeing and being seen.
IMHO, the main issue is that players tend to move their units too fast and then expect them to have seen everything in the general area.
Remember, if you use the full movement allocation of, say, and infantry unit...they are considered to be sprinting.
It is hard to spot a well hidden sniper, or scout unit in some trees 150m away when you are sprinting in full battle kit and in a different direction.

Slow down and you'll see more :-)

3. I think it is not meant to have a hex height = x meters.
It is a relative measurement.
I tend to think of it in meters. Height 1 = 10m
It works for me.

Good luck bro
SGT