Is there a trigger that can help reduce the amount of times weak nations get the rival army/navy mission?
My idea is that if you limit the potential to get this mission to only those rivals whose land/naval forcelimit is equal to or less than your own, that way you (and more importantly, the AI) don't get missions where, for example, Japan doesn't need to build twice their capacity in either their army or navy in order to 'keep up' with their rival, Ming. This would also help in the area of the AI spending too much on a military they cannot maintain and cut down on their inflation, but also help the player avoid skipping missions they simply can't achieve without a high cost compared to the reward.
The closest trigger I could find was "land_forcelimit" or "naval_forcelimit", but it looks like that only works for your country instead of the rival country? And that only lists a number instead of a variable THIS or whatever would be required.