I'm surprised I didn't see this thread earlier.
I've had exactly the same idea as the OP about a failed order allowing limited movement- and decided on the same restrictions. I was also influenced by Epic Armageddon!
The idea of allowing the General to issue orders to units isn't bad either, but doesn't fix what I see as the problem: Excessive chance.
There is a lot of chance in any wargame, of course, but Warmaster has more than most, since movement (normally taken for granted) can be harshly restricted by bad luck, or a crazy game win can come from excessive good luck- all in just a few rolls.
If an important brigade has been standing in your deployment zone for 2 turns, you can adjust the pace of advance of the moving part of the army and swap your characters so that the general can command those laggards. Once the general kicks them in their butts and makes them move forward, you can swap your characters back.
So there is a mechanism for it. If you're not using it, then the brigade stuck behind is probably not so important.
While good in theory, I've had games where either I or my opponent hasn't moved- at all. Sometimes for multiple turns. I've read battle reports with similar events too. The frustration is too much, and there's nothing you can do about it!
I know the Crown of Command, and to a lesser extent the Orb of Majesty can help here- but they almost seem mandatory for most people, and that's the sign of a problem. It's not right to encourage more people to get hooked on these toys, what's needed is to look at what has caused the addiction.
I've always thought that if the
is in the combat, it still has to retreat even if it's only in corner-to-corner contact. It lost the combat, so it has to retreat
Yes, the corner unit retreats as well.
Also, even if they don't retreat, the attacker is NOT flanked. To be flanked the

unit needs it's front edge to be in contact with the flank of

. Corners can be a bit iffy, but in this case it's clear that it's flank against flank.