Well... bear in mind that there's two components to maneuverability: Attitude and vector. In space, the difference between the two is a lot bigger than in atmospheric ships (and FreeSpace, and "traditional" Star Wars game physics).
The attitude of an airplane largely defines it's vector as well. There's a little variation, but in most cases the airplane is going to the direction where it's nose is pointed at; if it doesn't, you're in big trouble since normal airplanes lose controllability when the AOA grows too high, and at too high speeds flying sideways tends to have adverse effects (which is what happened to Space Shuttle Columbia) to the airframe. So within the approved flight envelope, it's safe to say that airplanes go through the air into the direction they are pointed at (exceptions confirming the rule) because the airplane is designed to stabilize itself in relation to the airstream.
In space, there's no airstream so attitude vector and velocity vector are completely separate entities. The vector changes are what causes g-forces (though in Star Wars there's no need to worry about those), and attitude maneuverability isn't really limited by any relative speed, but vector maneuverability is limited by the acceleration of the ship and thus the turn radius is defined by the velocity in relation to some point of reference. I should probably elaborate that this is the case in real life physics, so it doesn't need to be that way in the game, but some nod to that direction would be great in my opinion.
In a nutshell - in FreeSpace2 and X-Wing series, when your nose points at some direction, you're flying into that direction immediately. In Real life, you need to change the vector as well as attitude. Beyond the Red Line (and, assumedly, Diaspora) and The Babylon Project are somewhere in the middle; neither railroad or newtonian flight dynamics. If railroad physics is zero and full newtonian is ten, I think BtRL is probably at five or six at normal mode and 8-9 at glide mode, TBP is perhaps 4-5 at normal flight, and I think a Star Wars sim would be well placed on, like, something between 2 and 4.
If it is
possible, though, I would actually like two flight modes: One where attitude maneuverability is gradually reduced as reference velocity increases in order to keep the attitude and velocity vectors as similar as possible, and a more raw control flight mode where attitude maneuverability isn't limited, but correspondingly at high speeds the attitude and velocity vectors don't equalize as fast due to acceleration limits of the ships so controlled flight at high speeds would require more work. I don't know if I would want to see a full glide toggle on a star wars sim, though; I'll leave that question for the devs to answer.
Chief: Yes, I was always interested in aviation and WW2 era airplanes especially.