40k fan theory; Space Marines aren’t actually towering giants. But they’re well fed, selected for health basics and augmented with CRISPR etc where most citizens of the Imperium are basically feudal. So they’re actually 6’-6’2” where most humans are 5’4”-5’6”.
@Leucrotta Space marines are/were supposed to be inhuman monsters, and anything that makes them seem more human is failing at that.
Play up the brain-eating, acid-spitting abomination imo.