I just finished reading this excellent book about a British JTAC (Joint Terminal Attack Controller) in Afghanistan:Fire Strike 7/9
If you want to know exactly how a JTAC does his job, this book is for you.
One thing I didn't know before reading the book was that instead of requesting air assets due to a contact with the enemy, the assets are often assigned to the JTAC's ROZ (Restricted Operating Zone) continuously over a given time period, even before contact with the enemy. As one asset runs out of fuel, another arrives, and so on - with the actual platform assigned being pretty random.
There is a great story in that book about a time when the JTAC was assigned a Predator Drone whilst his unit was pinned down by enemy fire. Though armed with 2 "Hellfire" missiles, a JTAC normally only uses the Predator as a "recce" asset, to find targets to be hit by more suitable assets such as F15s. He describes how the operator of the Predator is probably some "couch potato" sat in an office in Nevada. With no choice over his available asset the JTAC tells the Predator operator to hit a Taliban position with one of the Hellfires. The operator is taken aback, and asks for the request to be repeated several times, saying that he has never used a Hellfire before. Eventually the operator is persuaded that he won't get into any trouble and launches the missile, killing something like 13 Taliban. The contrast with the JTAC in the field and the "couch potato" operator in Nevada taking out the Taliban almost like in a computer game was really interesting.
For FoF, it would be fun if some scenarios had a random air asset assigned, and if it was randomly determined if it was either a) on station the whole game, b) arriving in 1-3 turns, or c) departing in 1-3 turns. You could even have one leave after the first couple of turns, then a gap of a couple of turns, and another random asset arrive. The random element would make the game a bit more interesting in my opinion.