FlightGear has an F14b that can be flown in multiplayer mode both as Pilot or RIO to another player in the pilot seat. Weapons are simulated, but have little effect since FlightGear is not a combat simulator. However there is a set of scripts that allows for aerial dogfighting of sorts. All the cockpit and aircraft data can be extracted through multiple protocols, so driving external instrumentation is possible, though it might require a pretty large effort as there are no ready-made solutions. And both he plane and simulator are open source, so if you have some pet-peeve you can always modify it yourself to fix it.