the thing that really got me, and made this memorable, was the fact that the parallel world is actually destroyed

I agree that this is an exciting moment - but I also felt that it could have been made more exciting than it actually was, given how major an event it is. Maybe I'm just spoiled by New Who, with its much greater emphasis on emotions and character reactions, but I would have liked to see a bit more of that for the people left behind on the parallel world.

Oh, and big kudos for celebrating Invasion's dinosaurs in icon form. Somebody has to!