On the subject of painting within the interior of a boat, I have to admit on delivery of my families 'sailaway' the amount of oak faced ply does end up making look like an oversized coffin so I reckon a bit of paint, especailly the roof would lighten things up termendously and draw the eye away from the acres of dark woodwork which your boat currently has. Just an idea - its difficult to suggest alternatives without actually seeing the job in hand.
On a slightly diffrent topic, I must dmit it makes we wonder whether its worth lining a boat out in top quality solid oak as whether it be solid or manufactured, it all becomes knocked about and dark over the years. You might as well take the cheaper option and replace the linings every 15 years.
Just a thought