Fighting withdrawals are not as easy to perform in the field as you might expect. You say anything but a mob should be able to conduct a fighting withdrawal, but history does not support your statement.

The vast majority of defeats over history resulted in routs, not fighting withdrawals. In the context of MTW, I don't think you can expect your troops to "know how to conduct a fighting withdrawal on thier own." When do they stop to fire at the enemy? Who stays back to guard the rear and fight while others retreat? Which units should be engaged and which should be avoided? Answering these questions are fundamental to executing a fighting withdrawal-- these are questions to be answered by the general, not by a unit of peasants or spears or archers.

So, I think, it is how it should be-- if a fighting withdrawal is so easy to perform, then why dont you conduct it yourself? You will see it is not easy with a determined enemy (or 2) on your heels.

IMHO it is the height of skill to hold off 2 attackers whith ranged fire while you edge off the back of the map. I don't think you should be able to just click a key that does it for you. Work at it-- you will become a better player.

As for diplomacy, I agree. I basically play MP though, so it is not a big concern.