You can already set a budget for building improvement. Take that idea one step further and use a fund to buy Grain at a given price.
For cities you're already done, just set your price a little higher than the market and any time a merchant comes who's willing to sell for your price they'll fill your granaries first and then sell to the public. Result being your granary will always be topped off if there's a space of time between sieges, because every caravan bringing Grain into the city, and Grain producing villagers, will bring their stuff to the granaries first.
For Castles, it could be as simple as the castle's garrison, led by the governor if there is one, sending a group out to go to the nearest Grain producing village (there's nearly always one not too far away), and buying whatever they have until the granary is full. Again pulling off either the building fund or a new food fund. And being able to besiege the castle while half its garrison is out on a bread run would add an interesting strategic element to the timing of a siege
For added coolness, a Tightfisted ruler might buy Grain only at below market rates, so that the markets fill up first, and only then do the granaries get filled while a Generous ruler would buy Grain at well above market price if needed.
For cities you're already done, just set your price a little higher than the market and any time a merchant comes who's willing to sell for your price they'll fill your granaries first and then sell to the public. Result being your granary will always be topped off if there's a space of time between sieges, because every caravan bringing Grain into the city, and Grain producing villagers, will bring their stuff to the granaries first.
For Castles, it could be as simple as the castle's garrison, led by the governor if there is one, sending a group out to go to the nearest Grain producing village (there's nearly always one not too far away), and buying whatever they have until the granary is full. Again pulling off either the building fund or a new food fund. And being able to besiege the castle while half its garrison is out on a bread run would add an interesting strategic element to the timing of a siege
For added coolness, a Tightfisted ruler might buy Grain only at below market rates, so that the markets fill up first, and only then do the granaries get filled while a Generous ruler would buy Grain at well above market price if needed.
