I play most of my games solo, and sometimes, for the sake of speed, I make what I believe is the most logical decision. But there are plenty of times when it's not clear, or I want to make sure I'm not unduly influencing the enemy (i.e., playing against myself), or I want to give an opportunity for something unexpected to happen, so I use a 'decision matrix."
I use a D10 thusly:
1-3 = Most dangerous course of action.
3-9 = Most likely course of action.
10 = Goofiest, craziest, dumbest, most different course of action.
Example: An enemy infantry unit is sitting dug-in, with two of my infantry units not far from it, and one of my tank units behind them.
I would probably set it up like this:
Most likely is, the enemy team stays in its hole and fires its weapons at my rifle teams.
Most dangerous is, the enemy moves from its holes (hvy cover) to its right, behind lt cover, but then takes an AT shot at the flank of my tank. This assumes my rifle teams can't just gun them down as soon as they move. And for folks thinking this should be 'most likely,' I disagree, must guys don't want to move with enemy nearby, unless it's backwards.
Goofiest/craziest/etc... could be, they get heroic and decide to leave the cover of their holes and charge into close combat with my rifle teams; or, they're in a decent position, but get a little flustered and decide to bug out, that is, leave the holes by falling back out of LOS to my units.
The key is to figure out your three options before you roll, and stick to it! It's not perfect, but it works pretty well for me.
Like you, I also have Memoir '44 and I keep finding myself staring at those damned cards, trying to figure out a way to use them in solo gaming. The best I've come up with so far is to play my forces like BKC/CWC (activation), then pull cards for the enemy's activation. I haven't tried it yet, but the whole issue seems to be figuring out a good balance of cards to forces.
For example, you could pull one card per command stand, maybe two for the CO, then move that many units in that area (using the 'normal' Memoir '44 left, right, center. The problem is, that might not give you enough opportunities. You could try rolling a D6 per command stand/CO, though this could give you way too many moves, and you find yourself overrun very quickly.
I'd bet that rolling a D3 or D4 per command/CO is probably the best, though you'd have to do a bunch of playtesting to figure out the right ratio, and still realize you could have some pretty generous swings to one side or the other, that is, too much/too few activations in any given turn, or even game. But BKC/CWC, with the die-roll activations, can be like that anyway.
If you really got it nailed down, you could bump from one card per, to D3, D4, or D6, based on troop quality.
Certainly an interesting discussion, I'm always keen to hear what fellow solo-gamers are doing to 'liven' up the enemy. And this should be on the 'solo' board! Lord knows it rarely gets any traffic
V/R,
Jack