Oh, take some time to whip out the Gift of Health. This makes the berserking giants real powerhouses. My Hall of Fame Jarl got heroic toughness and combined w/ GoH the HP's were around 100. And I believe regeneration is based on maximum HP...

And if they ever bother to take afflictions, they heal in only a few turns.
Get a squad of woodsmen and herses, bless them and talk about staying power!
Only problem, though, is GoH is in effect only in your dominion, but you can't have everything...
- Humer