I've seen a lot of flight game's, in which I found that fuel is as important as Payload's if not more. Realisticaly, fuel availibility and use adds a dimension of stress and concen. When flying the F16 thunderbird at stage 4 afterburner, a full tank of fuel is used up in about 6 minutes. Adding three drop tanks would probably give about another 6 minutes of flight time. Whereas flying at 75 - 85% throttle will give about 24 -28 min of flight time.
First of all, the F14 tomcat is an excellent addon for Flashpoint, however I reckon the fuel lasts far too long. Decreasing the air time would not only increase the addon's realism but also adding more flight management stress and excitment.