HoneyBadger, while your idea is generaly speaking a good one (thuogh very reminicent of D&D rules), I'd have to say that (again, sorry
) it doesn't really fit into Dominions.
Such a huge variation as you are suggesting would simply make the game much too random, as you can't even estimate what unit you will get when you purchase it.
Furthermore, this will shift the balance of power much in the favour of mages, since a mage's HP isn't very important (sure, its nice to have more HP to survive a battle that has gone bad, but more often than not, your mages are sitting safely at the back of your army).
My idea as to how something similar could be made to fit into Dominions is to:
1) Keep all the stats exactly as they are right now.
2) Make it so each unit/commander recruited will have a random amount of HP between (HP + Size) and (HP - Size), when recruited.
Though either way, I'd rather see Dominions stay as it is right now, because I like knowing exactly the stats of the unit I'm about to get when I'm purchasing it :X
Also, as far as the idea goes thematically, while it seems to make sense to have such a wide range of HP because people can be really puny or really big and strong, practically, you'd expect anyone that has been
recruited into the military and is being
payed to fight will atleast go through some screening process and training, which should weed out "very weak hoburg children". Atleast in all grades of unit besides militia (which already has -1 hp IIRC) and PD (which traditionally is made up of the local population of fat unemployed people
)