Can you change the width (thickness) of the BAND in a Dial (ARCH) chart?
Please post an image of a desired chart and we'll see if we can add that option.
For now you might wish to use the Speedometer version, where you have a very thin border with the Level + Target + low/ good/ high coloured zones.
Under the View Style you will find lots of options to change the angle of the dial, format the needle, borders etc.
Hope this helps