Limited Open borders treaty

[Starfry]

Was playing one of my online games and had a situation where someone was gaining a win but I couldn't do anything about it since three empires were in my way.
I thought of a limited open borders treaty card where only strategic lifts can be used and unit must be a certain number of hexes away from cities to keep from spying.
Levels would be implemented in the amount of forces used where a level one would only use infantry/mobile units, level 2 aircrafts, level 3 tanks.
If the player can abuse this and try to gain a first strike move by placing units strategically, the penalty would be cutting off from supplies from their respective empires.

[zgrssd]

In the game as it stands now, moving through even a allies borders is impossible. And it would not be a easy change.
Strategic Movement consumes Logistics points that are leftover on the roads&rails. And your logistics points do not leave your borders. So that would be exactly the same difficulty to fix.

For the moment, it is impossible.