A SE England - Le Havre route would have a tough time attracting leisure passengers, given the LCY-Deauville route and that Rouen is only about an hour from Paris. Giverny is even nearer Paris than Rouen
A choice of Caen does at least have a clear appeal to those wanting to visit Bayeux and the D Day beaches (70 years this summer). Le Havre is not somewhere most people would choose to hang around for leisure reasons for longer than absolutely necessary