How about allowing enemies to collect taxes instead of you during take over.
I believe at the moment if your region is being taken over, you don't get the gold for that week - not sure if the gold gets pushed to the following week in which case you won't really be losing much.
How about allowing your enemy to collect the gold and food at a reduced rate? And maybe that rate will increase depending on how close the region is from being taken over?
If you want the tax gold and food stored in the region, you loot it.
Takeovers already do enough to abrogate the region owner's control over the region, I think.
I was hoping there would be a way to get that without burning the region to the ground :o
Looting for gold doesn't do all that much lasting damage, especially not compared to some of the more intense options.
When you control the region you gather the taxes. When you don't control it yet, you have to extort taxes by force.
Makes sense, no?