I don't think it makes much sense going with the ranges, since most high level resources you don't really need to keep track of.
Especially when you consider stuff like platinum ore or mahogany wood where the current state is always "much more than you can spend".
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As for the customizable bar, I think a good approach would be a checkbox in the options tabs allowing us to choose which components are supposed to be rendered on start of the game. Drag & drop would be nicer but I think way too complex to be implemented easily.