Genozide's suggestion concerning the guns sounds quite good. A medium gun would give the ship a bit more power. The ship probably would be rather fragile, so why not turn it into a glass cannon entirely?
The reapir work would be awkward. The Squid gets away with its redundant components as they're easy fixes. Balloons however are not. They're massive targets, and are a lot of repair and rebuild hits. The vertical movement of this badboy would need to be something amazing to make such a hard balloon repair and rebuild feasible.
that was one of my fears as well. Carronades would be really good against this ship, but on the other hand, you'd have twice the amount of balloon health and would only sink quickly if both balloons were down.
Also, this picture is from another game calles "Pure Steam." I never said to introduce it to GOIO the way it is, it just gave me the idea of having a ship with two balloons.