End it with Adama on the hill, next to Roslin's grave. That was the emotional high point and the perfect place to close the series. It's been about them since the start. On DVD I'm never watching it past this point again.
Also, scratch the whole "Let's abandon our tech" bullshiat. When Adama's sitting on the hill, have him looking out over the valley and various groups of people building cabins and planting crops.
And, really? Not only was the 150,000 Years Later refuckingdiculous, you had to go and ruin it further with a montage of robots while playing "All Along the Watchtower"? I wanted to break something.
Also, the happy ending completely spoils any significance on the part of Tori. When Tyrol learned she killed Cally I thought they were going to finally give Tori some meaning - her as a Cylon was a "WTF" moment purely because she was never a key player, and killing Cally was really the only important thing she ever did as a Cylon - but instead they went ahead with the peace anyway.
Alternate ending thoughts:
- When Tyrol kills Tori all hell breaks loose, Cavil is shot in the stomach and carried away by his Centurions, the Simon and Doral are both killed.
- As the Raiders turn back on Galactica, the whole Starbuck-entering-coordinates scene commences.
- Galactica jumps away right before the Raiders close on it. Immediately after, Racetrack launches the nukes just before she dies.
- As the colony dies, several Baseships, full of Centurions, escape. Cavil lies dying in the command center of one, says to the Centurions, "You think they didn't plan this all along?" He dies. The Centurions look at each other ominously.
- Galactica arrives at "Real" Earth. It's not inhabited by humanoids.
- All the landing stuff happens; the families, the characters, Lee/Kara, Saul/Ellen, Helo/Sharon/Hera; except for the "Let's Become Cave People" thing. Sure, they abandon their technology, but we see cabins being built and little paths being made.
- Adama/Roslin have their Raptor flight and burial. Adama on the cliff, next to the grave, watches the human race construct their wood buildings on their new home. His mission is accomplished. His journey is over. Cross dissolve to:
- Gaius and Caprica's conversation with the Angels . "All of this has happened before... All of it will happen again..." The Angels depart. Pull out from the planet to show the galaxy (alluding to Season 3) and pull back in a different part, with a shot of the Baseships. Cue the Final Four theme. They jump away. Blackout. End of Series.
At least there's still the Plan to look forward to before nervous anticipation of Caprica. Just remember that everybody thought a reimagining of BSG was a terrible idea... Skepticism for the spin-off should be taken the same way.