I would describe K/P just like Sandpiper described KwanHere I'd have to disagree. What you're saying is that K/P don't have range, which is true of many actors. For example, Garbo didn't really have wide comedic range (her funny performance in Ninotchka was more because she functioned as the "straight man" to the other characters), but you couldn't beat her when it came to drama. A great actor doesn't have to be great in every style, though some certainly are. I'd say that K/P were marvelous actors in terms of conveying romantic, lyrical, or tragic emotions.
There are many skaters who I consider wonderful artists, but I don't really see them as actors/actresses per se. Michelle, for instance, can act when she chooses to (see: Salome), but she spent most of her career focused on pure emotion/musicality rather than character or story.
For me they were a very musical pair, who showed lots of emotions on ice, but I'm not sure if I could call them great actors. But we don't need to agree.
In my opinion their acting was very over-the-top.Even more impressive were their predecessors, Bestemianova and Bukhin, especially Bestemianova. She had a plain face with rather outsize features, which she used to great effect especially in some of the couple's professional programs. One where he portrayed Rasputin and she played the young Tsarevich was simply beyond description. The way she conveyed the boy's fear of Rasputin's power was haunting in the extreme and would have looked good on any movie screen.
At the moment these skaters come to mind as good actors: Browning, Pluschenko, Petrenko, Yagudin, Witt, Anissina/Peizerat, T/D, Denkova/Staviski, V/M. But I'm sure there are many more.