I dunno, if you compare them side by side in character creation, the BT2 male is significantly taller than BT1/2/4 females. Also, I play a BT1 male (echoing the above poster's "leave him alone!"
) and he's way smaller. I figure it is something like this:
5'3-4" -- BT2 female
5'5-6" -- BT1 female (yes, they are a smidge taller), BT1 male
5'8-10" -- BT2 male, BT3 female
over 6' -- BT3 male
Not sure about the BT4's. I like these as they are, but it would be nice if players could use the bodies that Voss NPC's use, which are taller but slim rather than bulky. IMHO BT3 males look so disproportionately large at times because of their bulk moreso than their height.