Long Live the Confederation!
In addition to being inherited from the original BSG, all of that (the names, the Greek-derived Gods and so forth) serves a singular purpose: imply a connection between Battlestar Galactica and a very specific ancient culture from which its civilization has evolved.Actually, the space people in Battlestar Galactica are very closely connected to Earth. There are a lot of strong cultural and religious ties to old civilizations; worshipping a Greekish pantheon of gods, characters with Greek and Roman names (Gaius, Valeri, Agathon, Thrace), the UK title has a woman singing in Sanskrit (I couldn't verify the actual language personally), and other such stuff. The original show's big huge theme of "life here began out there" was one of the neatest things about it, and is why there are all of these cultural references to old Earth culture in the current one.
I mean, it's OK if you don't like it. But I don't think that's a valid criticism due to the show's specific effort to incorporate ancient Earth cultural elements.
Celtic folk music does not. It doesn't play up that angle at all... and it's a cheap technique - oh, military stuff, lets remind everyone of Braveheart!
I google'd for more information on the 'UK intro' and found this quote from the composer: "It was more that we didn’t want to make it seem that we were anywhere. We wanted it to feel very warm and human but on the other hand we didn’t want it to sound like this is Western Europe circa 1975, we didn’t want to give it one time and one place. I played around a lot with odd time signatures for the same reason. I didn’t want it to sound like it had a home here and now. That was kind of the trick to make it seem unfamiliar yet comfortable too."
That, again, seems wholly contradictory to suddenly having an episode scored in an entirely different and completely modern way.
I'm not clear on what you weren't being serious about. I bet any TV show would love to have a famous composer like the two you mentioned write their music.Trust me, I know. I wasn't being serious.