I'm going to differ:
Great looking bike, and it doesn't look "down market" from a regular Sports.
Since you have a Raleigh, why not strip this one and go the "club racer" look?
Don't change wheel size, nothing to be gained. Plenty of tires available. Do the CR18's, single-speed or fixie hub, convert to alloy cranks, drop bars, leather saddle. Make a sporty-sports.