Solitaire "urgency" track to make enemy AI launch increasingly desperate missions?

I'm making a solitaire card-assisted naval age of sail game (historical).
This mechanism is needed to generate the enemy AI missions for each 2-week turn period.

Sorry for the long post, but here's the wider context that I think you need to know:

Historical situation
There were 2 sides. Each side vied for naval supremacy to control of a body of water. But the balance of power was so fragile that the loss of even one major ship on either side could instantly lose the entire campaign.
This posed a dilemma for the opposing admirals: Neither one could afford to sit in the safety of the homeport and let the enemy control the map. But contesting control meant seeking a decisive battle -- and risking everything in a single afternoon.
If one side gained a strategic advantage, then the other side usually avoided battle and got blockaded in their homeport until they could build a new ship and restore the balance. So it was also very difficult to bring a reluctant enemy to battle. The campaign was marked by cat-and-mouse actions, where one side would try to draw the other out into a vulnerable situation, catch a smaller part of the enemy force in an inferior position, or tit-for-tat raids on each other's homeport/shipyard while the enemy fleet was discovered to be off at sea.

Available Missions:
Each turn, the human player assigns each friendly ship an area of the map, and assigns each ship to any of 6 possible missions: 1. Refit in port, 2. Training cruise in the homeport zone, 3. Escort supply convoy, 4. Intercept (available only in the homeport zone, but this also gives a force the ability to engage enemy in an adjacent zone), 5. Patrol (engage the enemy in any zone), and 6. Support a land attack.

The game uses chit draws to secretly assign the enemy AI ships their areas and missions. But an entirely random mission draw won't work. I want the AI mission selections to be somewhat intelligent, and to respond to the evolving game situation.

I'm thinking of having some kind of "Urgency Track" mechanism, which the AI selects more aggressive/risky missions or less aggressive/risky missions based on the points representing the level of urgency in the AI strategic situation.

I want something that can force the AI to risk decisive battle. Since neither side would intentionally seek battle unless they have superiority, battles should result either when both sides are evenly matched, by accident, by miscalculation, or absolute desperation on the part of the inferior side due to some massive external pressure. (Example: In 1813 on Lake Erie, the British knew they had a disadvantage in firepower, but sought battle anyway because time had run out and they had no choice -- their supplies were exhausted and their Native American allies were on the verge of revolt)

Any ideas? Do you know of existing games that use tracks that influence (and get influenced by) piece behavior, changing board situations, and card-drawn events?