To me, it's a bit of a toss up right now. 3 way tie in some respects, between Super Hornet, Sabre, and yeah,
@Blind Owl. I'm not sure that the ability to carry several cases of Canadian beer (24 bottles each, by the way) counts as "fighter" duty, and I heard he's not for sale quite yet, according to his wife. Soon though. Very soon. It won't be so much a concept sale, as a fire sale, if that makes sense.
There needs to be an in-game distinction between Interceptor and Fighter that we don't have right now, and the term "heavy fighter" doesn't currently make a lot of sense.
Combat wise, I really like the Super Hornet the most at the moment because you can fly and shoot with 1 or 2 man crew, and it's a hard hitter, but if we have subsystem targeting the single engine is going to be a disadvantage. Saber has some advantages or should at least, in maneuverability and atmospheric flight, but it might not hit quite as hard.