Wow, that's an interesting one. Where is the
furnace relative to the stove top? I am thinking about the air flow in the living space - would that make a difference? Probably not.
However, my second thought is that the furnace cold air intake is under the cabinets, and the furnace sucks a lot of air through the cabinets and the only make up air comes down past the stove top openings around the burners. My stove and the furnace are on the opposite sides of the galley, so I do not think I would ever see this, but it did occur to me that it might be good to keep some of the cabinet doors open a crack when heating. When you rebuilt the cabinets, you made them too airtight, would be my guess. Thought of a louvered vent in one of the doors?