Hey Ed, here are some observations on the new release that I have been testing during the last days:
I have been playing on a Windows 10 Convertible / Tablet. Performance is good, but the volume buttons toggle the main menu when in combat mode. And when the enemy is moving the volume buttons make the screen rotate.
One minor issue/bug: When picking up a soldier from hospital after healing, his ability scores still are reduced (due to injuries suffered). When entering the next battle the ability scores return to the normal values though.
Concerning the gameplay: The AI is throwing far less nades now, maybe because of the changes to the algorithm you made? And it drops less usable weapons. Before good weapons could be found all over the place after a battle. Now I have to take the broken weapons to repair. Even Leonidas didn't bring his G36 when he joined my team, only a handgun :-/
Concerning the AI skills: Great improvement! AI movement is less predictable and they move to very good places to take cover, flank etc. I also found the AI to literally learn from my tactics. When I managed to kill some enemies from a good spot, they just rounded up some snipers and waited for interrupt. This is great because it keeps players moving and stop camping in one place all the match.
I am playing on very hard and it is insane! Like a match of chess: when you make one mistake you lose :-) I know you don't want the AI to be unbeatable, but I think it is ok, it is beatable, it is just really hard.
You wrote that you will have to either reduce the amount of enemies, or make them weaker. I don't think you should make them weaker. I think the solution will be the campaign layout: if you make a player encounter enemy teams with about the same strength, the game is playable. But it is impossible if you make a team with a strength of about 1000 fight an AI team of 12000. So I think in the campaign layout the enemy strength could be reduced in some cities and that will do the job. You could also make better weapons available in the earlier stages of the campaign. In my opinion the most difficult matches happen when the AI has better weapons (AK47 against handguns/submachine guns for example, or snipers against AK47).