I started off this post with images, but it got too confusing O_O
Now I'll simply list the knuffels I DON'T HAVE, with a '+' to denote wanted and '++' most wanted. Eventually I want all knuffels, but those I like less are lower priority.
Darkness, Air, Earth+, Fire+, Light, Water++
Darkness+, Air+, Light, Water+
Darkness, Air, Fire+, Light+, Water++
Air++, Fire, Light
Darkness++, Fire+, Light, Water+