lol - actually there are video fics out there, a show on "imagination channel" that someone based on my handle, named M'reen's 7 <g> I laughed so hard that I stole the show's icon for my own.

Turn about being fair play and all.
It was a collage nickname - my roommate was Elisabeth and when pming/emailing her boyfriend I got tired of typing it out over and over and started typing E-beth, and he loved it and promptly named me M-reen, and it stuck.
But I'd take Zen/Liberator over a lot of ships - for one, it had a treasure room! But the M'reen 7 ship in the fic wasn't bad either <g>
I can see a certain amount of Mary-Sue ism in some of the alternate timelines, but not all, and never minded them. I think they often show the writers, tired of TV executives limiting the drama and never letting anything different happen, find a way to step out and let things actually happen and deal with the results, if only in short term - the result is there are usually more drama in an alternate universe than the main one.
In fact some of my very favorite eps contain them - in SG-1, But For the Grace of God, (that's the title I think) is one of my favorites. Having Sam and Jack ship wasn't the main reason, it was dealing with an invasion, failing, and then having to deal with it all over again at home. DK, one of my favorite writers and executive for Farscape, wrote that one, refusing to do just the formula, they go thru the gate, they fight, they come back, and instead veering the story down another path with the magic (dimensional travel) mirror.
Farscape -notice the nice segue that you'll see me bring things back full circle here - had a fantastic idea that you'd love about alternate time lines tho.They held there was one time line, but as you traveled down wormholes(made using black holes) it was possible to bring an Unrealized Reality into play. If you knew what you were doing, you could take a side step into an alternate reality, something that is created by changes in the time line and could become the new reality - but if you stepped out quick enough, it would snap back to the old path. If you didn't know what you were doing, or were plain insane, you could end up making the alternate reality the new reality, and the one you came from would be unrealized.
This also mean if you accidentally time traveled instead of just falling into an unrealized realty, you could make sure you didnt change history if you focused on fixing the first things you set wrong.
This was a fascinating idea, that every glimpse into an alternate reality was not so much alternate, but actually making duck soup out of everything you knew, and you had to fix it fast or it would stay that way - but eventually (rather quickly in fact) they lost sight of that concept and made these unrealized realities into plain old alternate realities, something you could visit and come back from by choice, only affecting events in the other reality. All about taking a trip, being gone and then back home for dinner to a reality that you left for a bit, rather than a deadly lesson in physics. I was terribly disappointed in them for that, as it was the coolest new twist I'd seen a show take with the concept.
In reality, I don't think we are actually protected by causality, and that a time machine could wipe out things - but we'd never know.