Actually this is a very valid point that I have been thinking for a while now... by making the measurements be from model to model you have eventually added the a new dimension to the game that we previously didn't have.let me try to explain.
Before we could only move on the x-y plane since everithing was mesured from base to base, now however you mesure to the model, and measure vertical distances wen moving. This means that we have now fredom to move in the x-y-z plane. Tjis at first glance may seem like a trivial thing but for game play it is gamechanging. Let me just give you an example.
Consider a flying unit with a range attack, our terradons for example. Lets say they are equiped with starstrike jabalins (range 10"). Now since they are a flying unit and now you can move in the x-y-z plane this means that during the movement phase tbey can effectivelly move in the z direction (UP) a maximum distance of 14", so now you can place your terradons in a place where no melee weapon can reach them but you can still shoot with your javalins. This is huge since the only way to kill them now is using other fliers, shooting them, magic, or prayers but infantry threaths are out of the game. Adittionally if you think like that than the rule that at first seemed really strange "swooping dive" now make sense.
This is just an example but this could be used in many cases, take for example lord croak and Make him fly in a similar way as we mentioned before, now he gets that much harder to kill.
What do you guys thibk about this I would love to know your thoughts.
Tetto looks Great by the way!
@Crowsfoot