I'm going to have to go with Wedge as well. In ANH he saves Luke with some very skillful piloting, blowing up that TIE a split-second before he would've rammed it.
In ESB he (and Wes Janson, gotta give props to the gunner!) pull off the tow-cable manuever while Luke--and nearly every other Rogue--gets shot down.
And in ROTJ, he gets the kill on the Death Star, and has the skill to live to tell about it.
Meanwhile, Ackbar's ready to pull the plug as soon as he sees theDeath Star's shield is still up...and then again as soon as the Death Star starts firing. For a brilliant military commander, it sure seems like he's got no spine.
That sigh JJ refers to, I've always read as a bit of relief at knowing he's not going down in history as the biggest wimp in the Alliance--and that was only thanks to Lando's "never-say-die" attitude and the extreme hotdogging of the Rebellion's "every man."
Why EU doesn't talk about a disgraced Ackbar being given his walking papers by "Admiral Calrissian" I'll never know.