I'll spare us the nitty-gritty, in-depth schematics and specifications, but basically T.I.E. Fighters are much faster and more maneuverable than Y-, X-, or B-wings. Y-wings are a bit slower and less maneuverable than X-wings. Likewise, B-wings are to Y-wings what Y-wings are to X-wings (specifically regarding speed and maneuverablility).
Y-wings pack far more devastating firepower than X-wings and their reinforced armor & deflector shield systems are considerably more rugged. Even so, B-wings pack even greater fire power than Y-wings and their armor & shield integrity are almost on par with them. However, B-wings have a very slim fore and aft profile, they're harder to track, and the're equipped with an advanced gyroscopic stabilization system. All these attributes combined make the B-wing a very difficult craft to destroy.
After playing First Strike like there's no tomorrow (and it's absolutely jaw dropping
). There are a few technicalities regarding accuracy on some of the craft. I'll name off the one's I can recall off the top of my head. For anything else, I'll have to go "refresh" my memory.

1) Both the Y-wing & B-wing are equipped with four more proton torpedoes than their default configuration.
2) I understand this next point most likely has to do with limitations in implementing it properly, but it would be great to be able to swing the B-wing's gyro in both directions. Logically, it probably would rotate a bit faster, but that's up in the air.
3) The A-wing is missing it's 2 Dymek HM-6 concussion missile launchers (with 6 missiles each).
4) There are various inaccurate sound fx (ion cannons, DL-44, proton torpedoes, etc.), but I don't know if that's because they can't be used or for some other reason.
5) The S3 model Y-wing's turret's ability to switch between ion & laser cannon fire (although, I must admit it's pretty cool).
6) Limiting ion cannons with ammunition. I'd personally include a recharge rate or overheat function for gameplay purposes. Possibly for laser cannon fire as well.
7) The T.I.E. Fighter's laser cannons are not fire linked.
Of course, ultimately, gameplay takes precedence over lore accuracy for this type of game. And ooooooohhhhhhhhhhh what a game it is. lol 
It'd be nice to have manual control over the S-foils, and I'm dying to be able to look around the cockpit interior for all craft & vehicles. I LOOOOVE that feature. lol
Artificial intelligence is no match for natural stupidity.