The main concern is that if the range is placed at the end of the cabinet run, adding a side panel could look awkward with just a 1.5″ finished end exposed. In that scenario, you’d either have a narrow painted strip with a countertop resting on top or a small finished edge alone, both of which can appear out of place. Ideally, try to leave at least 9–12″ of space beside the range. Not only will this improve the look, but it also provides some much-needed prep space while cooking.