Captain Janeway, of Voyager, never met a timeline she thought was above a little improvement.
Alternate timelines were huge in Voyager, and throughout the seasons I watched, I think I saw the alternate timeline theme no less than three times, if even that low a number. Even the last episode dealt with an alternate timeline, with Janeway going back in time to fix some shit she thought could have gone better.
I'm admittedly utterly fascinated about could-have-beens, even as I'm someone who lives in the present and apologizing for past-fuckups forever isn't my forte. In my head, I'm always re-visiting past scenarios where I think of what I could have said, or should have said, and how it would have played out. My life isn't the only thing that undergoes theoretical re-writings - ANYTHING can: current politics, stuff I see on TV, stuff I read, conversations I overhear... they're all subject to a little re-visiting so I can figure out what Could Have Gone Better.
History lessons, in particular, are subject to revisioning as I figure out what Could Have Gone Better so that the world is a Little Less Fucked Up.
I do think these re-imaginings are important. Unlike Captain Janeway, I'll probably never go back in time to fix that shit (I wonder if those guys from the 29th century ever held her accountable for it?), but at the very least, I'll have a definite opinion about How Shit Should Go Down in the future.