They're clearly "Bretonian", as far as the fact that they live in Bretonia. I would say they have a distinct culture from that of mainstream Bretonia though. That they're still getting the majority of new people from groups like the Green Front (purely Bretonian) would certainly push toward Bretonian.
I think there is a good reason to have Bretonian influenced ships though - they would have a lot of Bretonian trained engineers. But I think it'd be more interesting if they were Bretonian in ship but aesthetically much different.