Well, for the image of Charmander I would prefer just the
Bulbapedia one, as the images for their Pokemon are all the exact same artist (and, by extension, style).
As for the background, neither seems to fit. The one with Ash seems like something that would be better to use for every single Pokemon because it is so generic. And the rocky one seems better suited to a Rock or Ground type.
The ability area's background should definitely not have clouds. In general clouds should never be used for anything in design. Just keep it a solid color, either a lighter shade of pink or white is fine.