Another point to these is that the lighter ones also show more bright red highlighting in the face. That red crosses over partway between the lighter uniform and darker uniform.
An example of one that's partway between the two
http://www.ebay.com/itm/1909-1911-T2...item48622d3935
Most of the T206s I've looked closely at have both light and dark blue. Even the very light uniforms appear to have at least the light blue. The two Turners I see on Ebay both Sovereigns also have a bit of light blue at the bottom of the uniform. And the Stovalls all seem to have a light blue bottom button for all the uniform colors.
Cards like these are what makes me think the card images were reworked between series, especially between 150 and 350. And possibly were different between brands as well.
The Conroy hat stripes that Scot posted about in the past are one example that's clearly different between 150 and 350, and within the 350's there's stuff like Dygert having red or not on the lips. A very common "missing red" that was likely deliberate and gets little attention of any kind. Criger also comes with different color uniforms- gray or reddish brown.
Steve B