Barnabas certainly was much more of an "activist" rather than a "passivisit" in 1897.
One thing that keeps me coming back to topics like this is that time is so convoluted and paradoxical that it continuously remains interesting. I mean, if you look at the natural timeline of things: 1795-1840-1897-1960s-1995, it seems all jumbled up. But, if you look at if from the perspective of the audience, and thus, the characters, it tends to make much more sense even though it shouldn't-- 1960s, 1795, 1960s, 1897, 1995, 1960s, 1840.
I think it's fairly safe to say that Vicki isn't responsible for the convolutions that happened, as she was only replacing Phyllis Wick, who we can assume went through all the same things.
But, lets just forget the character's personal timelines for a second. Start with 1840. All that stuff that's happened, Barnabas is interfereing yet again. Julia, Stokes, and Angelique all pop up, all characters from another time. Mucking up of the timeline seems to be the in thing. So, what if all these people popping up is what caused Quentin in 1897 to be so conniving and evil, thus leading to his ghost haunting Collinwood in the 60s? Maybe in the original 1840, Angelique didn't visit Barnabas' grave at all. Maybe she did, and was assured that he was still there, so she left, without becoming involved in the events at Collinwood.
And it's completely possible that Barnabas traveling back in time caused the Leviathans to show up. They saw he was perpetually trapped in 1897, with no apparent way out, and decided to take advantage of it, using their last ounce of power to bring him forth, make him their earth-bound leader, and bring them back to power.
There's a million different ways this could go, and THAT'S what makes it interesting to talk about.