I remember when Naval Action was first announced i was so excited to play it but the single player content is shocking. I haven't played in over a year so not sure if the single player content is any better. If i'd known back then it would be MP focussed i would never have bought it.
Hopefully Sea Legends is more of a single player experience. But unlike Naval Action i certainly wont be buying until i know what content there is and if it's more single player focussed.