I thought having Han shoot first was a major point in his character development. Being the awesome badass that he is, and always will be, Han shoots first because he know's he'll die if he doesn't. That and he likes the smell of charred Rodian flesh.... Anyway...
Forward through the events after he meets up with Luke and Obi-Wan, Han discovers a side to himself he never knew existed, or, probably better described as a side that he pushed down because he felt that too much empathy was not a good sentiment for a Smuggler.
But he comes back just as Luke needs him. The change in his character from the self-serving, kill or be killed awesome badass from the start of the movie, to the reluctant, yet caring and willing to put his life at risk for others, awesome baddass that he turns into at the end.
Its not that we WANT him to shoot first, its that Han NEEDS to shoot first. It's of the utmost importance to the story!
Or this could just be a bunch of rambling BS due to three hours sleep, an 8 hour shift and five cups of coffee... Either way, Han shot first. End.