I have to agree. You can't have too much money and too many wars at the same time. I end all my turns by giving a percentage of my treasury to my peaceful neighbours to keep them from attacking me. Doing that and maintaining reasonable garrisons along the peaceful borders is an easy way to lose a lot of that income and keep the warfare side of the game manageable. I have even managed to buy peace treaties from the AI with large amounts of mnai (the last one I remember was for about 35,000 mnai), of course, only after soundly asserting my superiority over them. Just don't do this if the AI still has armies in your territory. Otherwise they'll just accept the gold and then attack you the next turn.
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