Without getting into it too much, I'm just wondering...why couldn't this be an alternate timeline show? We know there are several main timelines, the regular one and the mirror one, and of course the pre-and-post
First Contact ones, and lots of minor ones: in that TNG ep with all those other universes colliding, Janeway's timetravel adventures...why couldn't this be a timeline from just one of those, that ENT is just one version of what happened?
The only ep I really take issue with the "series finale". I think the season 4 finale was actually a nice cap to the series...I don't think it needed an actual "series finale", because that actually messed with the timeline and character development of ENT itself, and messed up the Pegusas episode of ST:TNG.
Then again, we could just give ourselves all a healthy dose of disbelief