I don't think they should have quite the same skills since they're obsolete, but I think Sairs should still ride a boat for their skills. They're Captains in KMS after all, why should they be standing on the ground?
Hell give them a flying ship, they can be sky captains! Not like other classes don't have flying skills too after all.
I honestly didn't like the battleship. I liked rapid fire way more, the aesthetics of it was very pleasing (even till this day I stand by that) Even back then when Battleship had a duration where you have switch between the two (rapid fire and battleship cannon)I enjoyed my glorious wings shooting bullets everywhere.