My guess the far right are your RIR/Lakenvelder mixes (the darker coloring coming from the RIR) as my BO's always laid a lighter tan tint egg.
Lady of McCamley
EDITED TO ADD: this egg chart from http://www.wilco.coop/stores/chickville/ which shows egg colors by breed pretty much as I've experienced (except of course it is an EE not Ameraucana as listed on their site).
Thanks for the graphic. It is great. This all makes me want to get a web cam. I don't the Buffs are laying yet. They are all the same age 5 1/2 months. I would be getting more eggs.