My opinion is that the gradient fills give it all a pretty slick look.
Is it overly complicated to allow just the legend colors to be sans gradient; referencing the gradient start or end color & pulling the legend colors from the RGB table array & ignoring the gradient stepping?
Or, perhaps have the legend text use the bar colors; removing the squares?
Personally, I would love to see the gradients stay (or optioned) &, like you, think all bars should reflect data w/ a common appearance.
BTW - thanks for all your time with all this (sorry if I opened a can of worms...

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