As for the style, sort of except perhaps a bit taller? I like how smooth your chibi's come out after the coloring. I really just want a bit more facial expression.
Specifics
Colors
Spire - Preferably a green eye color
Rika - Brown Eyes
Outfits should remain the same
Position
Sitting I suppose xD I'm not too picky, I just want the characters to be together and not warped from a weird angle. So I guess improvise to whatever fits your mood?
Background
Are we allowed backgrounds for that matter? All the examples are shown with a simple accenting color. If so, just a really simple grassy bottom, otherwise a nice shade of green or white.
Hope you didn't mind me stealing a look in depth into your gallery, perhaps the styling could be similar to this?