Your observations about Kaycee (is that really the correct spelling? Sigh) make a great deal of sense, but I'm by no means convinced that the writers are interested in making story sense. Story sense demanded that a main character become pregnant after Roslin's abortion ban, but the purpose of that plotline was to Make a Point. I don't think it's entirely unlikely that the Kaycee sub-plot is primarily intended to mess with Kara's head, and that petty concerns such as the importance of hybrids in other sub-plots aren't being allowed to interfere with that goal. We'll have to wait and see.

Anyway, the revelation I'm eager for is whether Kara's feelings for Kaycee are genuine, or whether they're a ruse to trick Leoben, or the result of derangement.