I wouldn't get too influenced by the 'how well will it sell in the future ?' niggle, you may only get the chance once, so chuck caution away and create what YOU want, after all tastes change over the years unpredictably anyway
+1
Looking at a few cars for sale regularly, the main difference seems to be between those that sell in 2 weeks and those that take 3-4 months. In the hope that I wouldn't be in a real hurry when the sad time comes, I would go for what makes me happy. Mrs F tells me that happiness is keeping our current 4/4. I am rather tempted by a Plus Four auto with Garnet wings and an ivory body on stainless wires with a walnut dashboard. I would go for a black interior while Mrs F (in the rare moments when this fantasy is discussed rather than rejected) would opt for a Magnolia interior. That would be a compromise that would be good to get to.