use more horizontal space for the 10x10 grid and less for the other parts: on the small map, the troop counts remain the same size as on the large map and the grid squares appear to be too small when u downsize the dimensions from 800x800 to 600x600.
the columns are numbered from 1 to 10, so the dropdown list display order, when playing a turn, is 1, 10, 2, 3, 4, 5, 6, 7, 8, 9. i recommend that u use 0 to 9 instead, so that the dropdown list display order becomes a more logical 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
change vessel to frigate. any ship can be called a vessel, while a frigate is a relatively small warship.
in most navies, cruisers are generally larger, and have more powerful guns, than destroyers, so ought to have a larger bonus than destroyers.
rename the command center as the bridge, since bridge is the term used on both naval and commercial ships.
reduce the bonus from +2 to +1 for the gunboats and submarines, since they're the only ships that can bombard the other side.
with only a +8 bonus, the aircraft carriers are likely to be ignored in most games. they need something much more powerful, such as the conditional ability to assault all ships on the same side, if all 8 regions are held. an alternative is, as DoomYoshi says, to remove the aircraft carriers and add more of the other bonuses.