Suppose you had to breed a clone army of supersoldiers (infantry), what size would you make them? It would be tempting to just say 7ft 400 lbs, but there are a few things to consider:
- Strength doesn't scale linearly (5ft gymnasts have a better power:weight ratio than hulk strongmen, but obviously don't have as much absolute strength)
- High endurance aspect of military life
- Need to be a certain size to drive/fit into certain vehicles
- Need to be light enough to be quickly dragged out of action if wounded
- Need to have a base minimum level of strength to be able to lug around gear
- Need to be able to quickly cover obstacles while wearing said gear
- Smaller guy = smaller target
So take, for example, a 150 lb guy vs the 400 lb hulk. The 150 lb guy would have a much easier time rucking for hours and climbing over obstacles with the issued gear (which weighs the same for everyone), but the hulk will have pure brute strength and be better for certain roles (e.g. breaching).
What height/weight would be optimal, assuming everyone in your army had to be 1 size?