This isn't necessarily an issue but I will raise it out of curiosity. I know Commandos don't set off spike traps but they do die when another unit sets of a spike trap and the Commando happens to be with those troops. Is this intended?
similarly, merc infantry are not targeted by enemy towers, but if a redoubt or a mortar is shooting at something else and the mercs happen to be standing there, they get hurt
It's the first time I've noticed it happen. It surprised me because I couldn't understand at first what could have taken out my Commando. The replay confirmed my suspicions though.