I've tried having Edgecomb mixed at 50% value, but it totally changed the color, and just looked like a chalky gray. - Does anyone know of a LIGHTER version of Edgecomb?
Yes, cutting formulas is not a reliable color strategy. The majority of the popular near neutrals like Edgecomb Gray are especially not good candidates for the cutting formula thing. Most will result in odd, unbalanced grays that just aren't pretty colors. Which is why I'm constantly advising against cutting formulas.
For a lighter color that's very similar to Edgecomb in terms of hue family and chroma just lighter take a look at BenM's Fossil AF-65.
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lighter shade of edgecomb
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