My thoughts are this.
Filmation Skeletor almost never rode Panthor. Usually only rode him in the comics and paintings. Filmation He-Man rode Battle-Cat a lot obviously.
Since Jerry has said a Filmation Battle-Cat is in the works I figure have them swapped. The realistic line could have Skeletor on Panthor, and of course Battle-Cat alongside He-Man.
The Filmation line could have He-Man riding Battle-Cat and Panthor with Skeletor maybe in something like this.
Jerry has split up some fan demands with the current combo. Some people have been clamoring for a realistic He-Man while I think a lot more folks want Battle-Cat. The He-Man statue from the combo is well done but I can't see a lot of interest in him alone. This combo is all about Battle-Cat and He-Man is thrown in for incentive.
I mean I can't see a straight Filmation Battle-Cat alone selling that great especially after this combo even a year later when this will not have been delivered. People that want Battle-Cat alone will get this and those holding out for a straight Filmation will be an even smaller lot.
At some point this line has to have He-Man riding Battle-Cat especially if there is to be a Filmation Battle-Cat. Next to the transformation sequence it is some of the most recognizable and powerful imagery from the show.
Skeletor on his bone throne is just too awesome to pass up and was a large part of the show. I think a dio like above could sell.