Apollo and Sheba begin a passionate and intense romance, full of angst, with lots of personal battles.
Starbuck, true to his words to Chameleon, sticks to his guns and tells Cassie that he really doesn't feel able to commit to the idea of marriage and family until they find Earth, or at least an environment in which he could feel secure raising a family. (settlement? if the Cylon threat was somehow eradicated.) She has to decide if their chosen flight paths will align, or not.
Cassie starts furthering her med tech training, focusing more on her career.
Athena finds a purpose, other than to fill in plot holes. Just not sure what.
That whole Baltar situation would have to be brought to a head. Would Adama actually drop him on a planet with communications and survival equipment? Or would the wishes of the people and the Council change how the traitor was dealt with? I can't see Adama being alone in making this decision, despite his pact. Frankly, I'm surprised no one made an attempt to kill Baltar during his imprisonment.
Muffit is tragically killed. And they're all out of spare parts.
Cain returns, but with a twist.Let's twist again, like we did last summer . . .
Chameleon reappears. I don't see Starbuck keeping up a friendship with the old boy, just out of a love of gambling and conning. He would gradually become less available to Chameleon, due to time constraints. Most of his living would be done on the Galactica, after all. Chameleon would realize if he wanted a relationship with Starbuck, he would have to fess up. Then face the music.