I too am trying my hand at giving more survivability to my Swordmasters. I'm fooling around with the notion of two mages using life, one having the seerstaff and giving him throne of vines and regrowth, and the other hoping for toughness and whatever else finds me.
One thing I think some failed to notice is that throne of vines is a remain in play spell. So, until that miscast, it stays in play boosting other spells.
Also, remember that upon every successful cast in lore of life, a unit within 12" regenerates one wound previously dealt to a unit (hey look! that arrow through his neck doesnt seem to bother him!).