I still think it would be a cool extra surprise if it was revealed in Sith that Obi-Wan was actually Luke's real father. Yeah, the OT is awesome and Darth/Luke still resonates, but it's almost like, in those movies, DARTH is Luke's father. The PT Anakin's character is such a whiny douchebag that it's a bummer to think he's Luke's dad. It would almost make more sense since Obi-Wan is 10x more noble of a character. Anakin could just *think* that he's the dad because he was with Padme, but Obi's unrequited love for Padme could've culminated in one night of bliss while Anakin was out doing bad Dark Side stuff. Or something. Crazy, I know, just some interesting speculation that I started thinking about when I saw ROTS.

With Obi-Wan and Padme having more chemistry than Padme and Anakin anyway, and if there was no OT, Obi as the pop would be neat. To me, anyway. Like, if only the audience, Obi-Wan, and Padme knew, but Anakin assumed it was his.