Would never do it from Zebrugge again - way too far.
Prefer heat to rain (mad dogs and Englishmen)
IMHO, one of the more enjoyable ferry routes to the Classic is the Portsmouth to St Malo, overnight crossing on the Wednesday.
Time on board for a superb Brittany Ferries dinner, a decent sleep and breakfast before disembarking. Lovely roads between St Malo and Le Mans and the pleasure of many classic cars enjoying the same route.