The ability to move through any number of friendlies or allies (as long as you have enough movement to get to a clear tile past them, so you would be able to pass a maximum of 3 friendlies/allies if you could make each hex with 2 AP) is very necessary. In big battles with lots of allies you often have to take the long way around, and frequently you can’t move at all because allies are in the way. Also, being unable to move through more than one of your own mercs can be deadly on maps where there aren’t many paths to move, such as forest maps. The AI already has the ability to move through more than one of its own troops, so all that is needed is the ability for the player to be able to move through any number of their own troops/allies and for allies to be able to move through the player’s troops.
Also are you going to make sure the AI allies don’t take your mercs into account when making decisions?
