Hi Charles,
If you are hired on a long-term basis you can definitely look into some more radical innovations for this product.
From my experience I agree that doing early user studies is of incredible value. The least you can do is an in-context task analysis and think-aloud or co-discovery protocol. You will get an overall field for the design landscape and just with visual composition you can improve much. If you go into the fundaments of HCI like suggested with Norman’s DOET, I also suggest reading up on the Frogger framework:
and Rich interaction as developed by Joep Frens: http://alexandria.tue.nl/extra2/200610381.pdf
As designers we need to start thinking beyond the WWII-era push-button, sliding and turning paradigm.
One cost effective solution can be capacitive sensing.
I suggest going at least for a multimodal approach where controls are not only distinguished by position and accompanying icon but also in other aspects like shape, texture, how they feel and make a mapping between the controls and their effects that makes sense in the minds of your specific customers. Also a clever integration of functions into one control (‘stacked actions’ in IxD terms) can be a great selling point for products, as we have seen with BMW’s iDrive.