Maybe it doesn't have to be confusing...
Try this
Take a look at this page
Krimson Queen Hoya (Hoya carnosa 'Tricolor')
Scroll to the bottom of all the database pics and see where the plant combo photos are. It says "This plant is tagged in:"
and there are two plant combination photos there with plants identified and tagged. Hopefully not too confusing..
Now
Imagine another similar section down there labeled as "Comparison Photos" with a photo of the leaves of Krimson Queen and Krimson Princess side-by-side identified and tagged.
And perhaps Lin's perennial comment
plantladylin said:Krimson Queen has green in the center of the leaf and white outer edges.
Krimson Princess has white in the center of the leaf and green outer edges.
Now, would that be confusing or helpful?
Personally, I think it would be fabulous
and Lynn could post the photo every time she explained it.