In terms of tactics, I think a double strike looks better than the first strike. With the first strike, only Alex's pikeman seems to synergize well, and even that's not certain... Unless you're afraid of unexpected attacks from the opponent, but in my opinion, it's better not to get caught in those unexpected attacks, not to mention that the first strike won't save you from archers and mages.
In terms of tactics, I think a double strike looks better than the first strike. With the first strike, only Alex's pikeman seems to synergize well, and even that's not certain... Unless you're afraid of unexpected attacks from the opponent, but in my opinion, it's better not to get caught in those unexpected attacks, not to mention that the first strike won't save you from archers and mages.