Ideas and suggestions.

In "version 1," there was experience gained from troops, and the stacks of viv-angels were larger in number. Also, antimagic was a multi-school spell, so it was present in almost all final builds. Because of this, there were no problems with arcanum.

What you described doesn't affect the fact that this spell clearly deserves to be level 5. I would say it's clearly more useful, stronger, and used more often than sacrifice. Swapping their levels seems like the optimal solution to me. No one will shout "hooray!" when they get a level 4 sacrifice in a shrine.