Hi there, I have just commented on these rules on BGG and thought I should share my thoughts here as I may be overlooking something obvious? What I said was "I have not had a chance to play with these rules yet, but would make these two observations:
This isn't a set of solo rules. It is a mechanism for deciding on limiting the choice of cards available to you each time. Despite having a whole section entitled "Command Card Play" there is no guidance on selecting the actual card for play. It is like the old cartoon with the complicated process, and in the middle a black box with "here a miracle happens". This bit, deciding on which card to play, what to play it on and what to do with the ordered units is actually what is needed by a true solitaire system, and is completely missing from these "rules".
The other point is that I am not convinced that there is any benefit to these rules over simply playing each hand as it arises as normal, just playing both sides. Indeed, it rather detracts from some of the strategy of trying to build a collection of two or more cards which when played sequentially allow your cunning plan to unfold, for me an important part of the game. The only bit of these I like is the management of out-of-turn cards, which might be worth playing with.
I enjoy playing solo by just playing both sides, and think that the constraints of available cards prevent the player from favouring one side or the other too much. But to see a solo system that seems to do the whole job for one side, Hostile Tactical AI provides some ideas, and on its page here has an implementation specifically for Memoir '44." Cheers, Matt