Add an option for "normalised" soldiers, where new recruits get a randomly distributed stats quota.

Set a quota based on half the difference between max stats and min stats in the ruleset. Set most stats to the min, randomly roll bravery, subtract the difference from min bravery from the quota, and then randomly pick a stat to increment until the quota is reached. All soldiers will either be good at something or average at everything, but there's still no guarantee you'll get soldiers whose strengths you like.