I second (third/fourth/fifth for some!) many of the ones already mentioned, especially the Rebel Yell jive, the Ballroom Blitz Blackpool dance, Love Sex Magic dance and last year's rememberance day dance. Wasn't Jo singing live on the latter? It was a nice touch.
In defence of the themed dances, I think this year has been MUCH better than the last few years for pro dances. The three standouts for me have been:
Movie week with Jo, Aljaz & Giovanni. Definitely become one of my favourite pro dances ever!
Halloween week with Brendan, Karen & Kevin.
Week 2 with Gorka & Oksana. A kind of Romeo & Juliet theme. Oksana looked incredible.
I hated the one set in a clothes shop or department store or whatever, though. Those type of dances (had a lot of them last year) give the strong themeing a bad name. I think when there is a proper storyline and a focus on two or three dancers, like the three examples above, it works a million times better.
In an ideal world, I'd like to see a mix of classic pro dances where everyone just dances great content to a great song, smaller pro dances with just two or three pros being showcased, and themed dances like the ones mentioned above.