Reward Program Enhancement

[JimNL]

I really could use an enhancement to the Reward Program. I would like to have a selection of products in a category for Buy 2 Get 1 Free. The problem is that there are multiple price levels within these products and I would like to make the free item equal to or less than the price of the other 2 items. Currently, the program makes the 3rd item added to the cart free. So, I could add 2 $16 items to the cart and then add a $29 item to the cart and the $29 item would be free.
I have spent an entire day trying to create a workaround for this (without programming it) within the reward program, but nothing works properly.
Just to be clear, here are some examples of what I would like. All of these products would be in the same category that would be used for the Qualifying and the Reward Categories.

-Add three $29 products to the cart, one $29 product is free
-Add two $29 products and one $24 product to the cart, the $24 product is free
-Add one $29 product and two $24 products to the cart, one $24 product is free
-Add one $29 product, one $24 product, and one $16 product to the cart, the $16 product is free

Thank you!