Yu-na's jumps are great, especially 3F and 3Lz. She gets so much height on them. But I can't get into her LP program this year at all. Aside from being amazed by her good jumps, the rest of it doesn't grab me much at all. The music is not especially easy to listen to (in terms of harmonic structure), nor especially exciting (building like Lambiel's), and her poor posture really detracts from the performance aspect. Why can't she just keep her back up, point her toes, turn out her knees? I feel like she goes from pose to pose a little bit, and that worked well last year for the Tango of Roxanne SP, because the music hit periodic highs and went well with this kind of skating. The other quality Yu-na has naturally is a sense of lyricaity that plays to the tenderness of the audience, and that was demonstrated splendidly in her Lark Ascending LP last season. But Miss Saigon neither had these syncopated strong beats, nor the lyrical soft parts that touch the audience's heart; in short, it didn't take advantage of Yu-na's strengths, and instead emphasized her weaknesses (bad posture, rough transitions -- all these are in relative terms of course, not compared to the average skater, or even the average elite skater, but the best skaters, and the strengths she has in other areas). I really feel like Mao Asada ought to have received higher PCS's, at least what she got at the last WC, probably a little higher, since the choreography (skating went better with the music) and performance (her posture/positions have improved) were better in this case, while Yu-na's PCS should not be quite as high as they were. Mao made some grievous errors in the SP, so I won't argue that she definitely should've won the GPF. But at least in the LP, she should've won by a more significant margin, by at least 4 or 5 points. But... again, I've never really understood the PCS system -- I really wish the CoP would break down the PCS like they do the TES, so the skaters as well as the audience can understand why they get the scores that they do!
Your impressions jive with mine.

I actually think the 'Miss Saigon" music cuts in Yu-Na's LP are good. Starts off with the explosive loud part, moves on to the slower and more tender second half, etc. I actually think the middle part makes Yu-Na's LP. 'Sun and Moon' sounds so beautiful in solo piano, and Yu-Na hits the spiral on the perfect beat when it begins. She really exhibits such tender expression (especially with that move she does where she clasps her hands and raises them to her face), and I really think the slow section is the best part of her program.
I don't think sporting broadcasts' goals are (or should be) to leave the audience on a baffled cliffhanger. But anyway, I think ESPN did try a little harder in the past to explain the scoring, though never too hard, which may be part of the reason in the decline of TV viewership. This year, having lost its broadcasting right to skating events, I think ESPN has less incentive than ever to invest in a thorough, well thought-out explanation of how CoP works.