[Ygorl]

Experience already does this, to a limited extent. The difference between a group of troops with two stars experience (about the most you generally see) and a green group is pretty major; still, the difference between those two-star troops and, say, a pack of lamias or wights is even bigger. Perhaps that's as should be, however. National troops are useful until you've researched the ability to do something better - that research represents an additional cost.

I wonder, actually, if things might be more differentiated by concentrating the summons into a small number of schools. Right now, every school except Evocation and Thaumaturgy gives you a way of putting together an army that will stomp any hired army (in the case of Alteration, that army is assembled on the battlefield), so almost no matter how you research you're going to quickly render your national troops obsolete. If all these spells were moved into one or two schools, then unless you researched those schools, you'd have to rely on your hired guys. These would probably be buffed by the spells or items that *are* in the schools you researched; your buffed hires would be going against the enemy's unbuffed summons, and it might still be a good match.

This could even make an interesting mod...