I agree. This seems to be the AI's primary method of "warfare" - send a load of one-two unit stacks running around your country breaking everything so you have to fix it by way of micromanagement.

No standing armies, no big battles, just a load of piddly two unit stacks to chase around. The worst part is that even if you send cavalry against them and defeat them they can retreat further than you can chase them in 1 turn and even with 1 soldier they can still damage your resources - so you spend most of your time forced to chase these two stack armies around until they are utterly exterminated.

WHICH. ISN'T. FUN.

The worst part is that if the AI just put all these little two stack armies together they'd have a decent force which they could use to at least present a challenge rather than a minor nuisance.