[LoloMo]

In MP it definitely just serves to increase micromanagement. Before their capital gets taken over, people would send all their stuff to an ally, after the capital is taken over, send the stuff back.

Capturable site would be better. I would suggest adding a site to each capital only national site that mimics the national troops, but at a slightly lower stats to reflect non native conquerors recruiting them. Perhaps even eliminating sacred status, or increasing costs. Would require a big mod though.