Bossman showing up would be pretty good reason for Blair and Angel to "cool it," keeping their feelings pent up untill the strain of the WC2 events
Well, the movie itself says very little about a Blair/Angel relationship. With the exception of our most recent exile, we've all kissed girls before without ending up in relationships -- it's something that's particularly common given the extraordinary circumstances under which Blair and Angel were reunited.
(Furthermore, the reverse is just as easily true; there's no evidence in Wing Commander II that Blair and Angel were never together... they certainly fall into eachothers arms fairly easily.)
Now, obviously, I'm sitting with my back to Pilgrim Stars. I implore you, lovers of the movie debate, to finally raise this to the last level and start a grand Pilgrim Stars thread. There are many elements of the novel that I haven't yet worked out in my own mind - if we put it to the test of a Forums debate, we can work out the kinks and put it to rest forever.
I live in both constant fear and continual hope of the Pilgrim Stars thread, which I predict will someday come to begin again and end all movie debate forever.
(As an aside, there's some other evidence for an earlier Blair/Angel situation - if Angel dies in Super Wing Commander, her 'ghost' quote at the end of the game is about how she was in love with the main character.)
Now, Bossman... obviously, we don't yet have a 'canonical' explanation of Bossman, but I do have a favorite theory. I'll readily admit that it's the loosest of the movie points still discussed today - and that's saying a lot, to be honest. I never thought I'd feel good about the Iason or the or (for a time) even things like the accents. In general, though, I do. Time and debate has worn them smooth, and I'm proud that we've accomplished that here.
So, Bossman:
Here's the rub: The Confederation Handbook gives us a detailed explanation of Bossman's death, in the form of a letter from Angel to Bossman's wife.
Now, just watching the movie you should notice that there's obviously something odd about the situation. Even if we had only the movie to go by, we would have to ask ourselves this question: how likely is it that a pilot will be killed on a combat mission... but that his single person fighter will survive and return to its carrier?
I would wager that it was fairly uncommon for Wildcats and Hellcats to outlive their pilots all the way to fighter recovery in World War II... and space is an infinitely larger and more complex landscape upon which to perform recovery operations.
So, then, what's the story? The aforementioned letter makes the following case (or retcon, depending on how spiteful we're feeling about the movies script): "However, the enemy managed to damage his engines in a way as to cause an overload in the reactor core. Your husband died of radiation poisoning from the core overload. The radiation was of sufficient intensity as to kill him instantly. The Kilrathi did not make any attempt to salvage your husband's Rapier."
Very pat -- but does it remind you of anything? Yes! End Run deals with just this sort of letter home:
"I'm sorry, I forgot your brother was part of the defense team that got caught."
"It's all right," Jason said quietly, "the letter said it was quick and clean."
"Of course," and her words were a bit too hurried, though sincere.
There were certain things in life that you clung to, even when you suspected they were lies. The letter to his mother from Joshua's sergeant, which described a heroic death, cut down painlessly by a neutron blast, was one of them. He didn't want to think of the alter-native, the fact that his brother might have been taken alive.
It shows up again in the same novel, when Jason writes a letter home telling a mother that her son died heroically (when in fact he actually panicked during a training exercise.
But there's our in -- the idea that the letter home is a lie to console the loved ones. Angel tells Bossman's wife that he died instantly because that's how such letters are written and not because it's necessarily true. He could, in fact, have been captured.
So, I posit that Bossman was in fact captured by the Kilrathi - and his fighter was abandoned in space by them afterwards (in fact, this sequence of events happens in one of the Wing Commander III news sequences!). The story of his escape is one that can be told by some better writer with some official blessing in the future.
On the other hand, he may simply have ejected and been lost - consider Vanderman in Fleet Action. The crew of the Tiger's Claw (!) had long thought him dead, when in fact he ejected and survived for a time on an uninhabited planet before being recovered. So too could be the fate of Bossman.
The Hakaga carriers are a perfect example for capships, and to me are more awesome than the Star Destroyers from Star Wars (I'd go so far as to say George Lucas should incorporate the Hakagas in another DVD release!! 
)! To see the same elements in the movie, with the dark-blue or black color schemes as it was shown, would have made it that much more exciting. 
