Aside from their usual playlists, in concerts I always love to see artists do their own interpretation of songs by other groups/artists. Its especially interesting when they take on a genre outside of their norm.
Cant think of any Korean examples at the moment but a few english one are Tori Amos covering Nirvana, Jewel covering the Cranberries or Taylor Swift cover of Eminem. Sometimes its really good, sometimes really bad, but its almost always interesting.
I wouldnt mind seeing Kara doing something way out of their comfort zone just for the fun of it
Just as an after thought, I wonder what Kara would sound like doing a cover of Bruno Mars' "Grenade"
or for a Korean cover, imagine what they would sound like on Bany Yonguk's "I Remember"