I propose the addition of more managers who can be assigned to various, more specialised jobs. There could, for example, be a kitchen manager who creates butchery, cooking, milling etc. jobs according to your preferences.
Communication
The managers would communicate, of course, with you and with each other, so that if, for example, the kitchen manager notices the stocks of flour are running low, he'll want to order more wheat milled. If, then, he notices the stocks of wheat are also low, he'll get in touch with the head manager who'll get in touch with the farming manager, who'll make sure a fresh big batch of wheat is planted for next harvest, at the expense of those crops that can be spared.
Creation
However managers are created is another matter. One could simply get the ability to assign them, once a manager noble has arrived, or perhaps they would arrive after the manager noble, when your production in their associated fields has grown enough. Perhaps the first dwarf to achieve legendary skill becomes one?
I honestly don't have a good idea, but I personally wouldn't like to have to wait for a legendary cook before I get a kitchen manager, because that'd never happen for me at the present rate.