I really like them, but I understand the problem and probably would look for something more natural myself. I can tell you what I would do, but that includes the risk of messing it up completely. I'd try breaking up any patterns and use different rust shades in irregular way, like flicking or stippling. I'm using very dilluted dark browns like burnt umber up to cadmium yellow and even skin tones for rust, so there's many options to create interest. I also like to use chalks in white spirit to create a crusty appearance. Ususally, if I don't like it, I just paint over it again, so the old rust colors get worked into the recently added ones until I think it's ok.
It might also be an option though and pull it back a little, just in parts, to make it look natural and create contrasts.
It might also be an option though and pull it back a little, just in parts, to make it look natural and create contrasts.