Yikes, a ten mast dreadnought and a super crew! I like both of them, though I’m wondering how BA would work on the ten master. I notice you specified submarines, not submerged ships, any reason? I think the cargo of 4 keeps the Wrath from being too powerful, kind of like my handling of the Yaochuan and her ability to submerge.
Diabolos is quite powerful, with the right rolls or UT set ups he could very quickly eliminate entire battle fleets or possibly entire factions. I’m looking forward to his eventual use in THC, it should be fun and interesting to see how that plays out.
Ability: This ship cannot load treasure. This ship ignores terrain when given a move action.