The problem with this, is that it doesn't fit with nature. That's kind of what the Enchantment sphere is for, I'd say. Recon units are most known to spend a lot of time in the outdoors, and know hot to make poisons, etc, so something that benefits only them is good in the nature line.
I don't really see the nature link for Enhanced Weapons. it kind of just sounds too similar to Enchantment I
Agreed, although I see no reason the poison effect can't be expanded. Why can't melee use poisoned blades? Why can't archers use poisoned arrows?
That's much more along the lines of what I was getting at...though I can see Warkirby's point about dumb melee types dying by the truckloads from biting their fingernails before washing their hands.
I would just like to see Poisoned Blade expanded so that all units get a bonus from it, and was trying to come up with a way to keep it like it is - Nature based - but give all units some type of bonus. Hence, better bows via better wood, better armor or shields via better wood, poison as it...all nature based.
Nature - at least imo - is one of the weakest spell spheres out there atm considering how popular it is and needs some buffing.
There are other good ideas though as well. I like the entangle idea - a mass root essentially (I hate to say this coming from a hating CC mmo background - but this game could actually use a little more CC) - is a good way to buff this line too.