I agree with you about some of the scheduling that is a bit odd, but regarding NCL-MJV, I think its an excellent idea, they have a QC a/c sitting around all day, so why not have it out earning money on a route not already served from NCL?
And regarding the 757s, they must be getting them cheap, so the extra seat capacity should = extra earnings, and the 757s will be better suited for the longer TFS and any other Canaries, especially off of LBAs short runway.