I'm certainly not saying that there isn't potential in the concept.
BUT!
Majority of gamers aside (the majority of players don't play SHIII, period) - I think it's safe to say that virtually every SHIII fan would much rather see a completely polished campaign and better-modeled sub to play in that campaign, than a half-finished sub and half-finished destroyer slugging it out somewhere in the half-finished Atlantic :hmm:
I think the Ubi team here is still learning to make single-player subsims. Let them get that single 'sub' part right before demanding a destroyer.
I think it's fair that most of us want a solid-modelled sim that works properly offline before something that goes well online :hmm:
Plus, for the aspiring sub-hunters, there's a fifty times more solid and feature-filled DW, where ASW is a little bit more brains than just making quick and dirty guesses at where that sub is and dropping a chock full of charges over it
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As far as a single player escort game...
What I think would suit things better is not a destroyer sim game but a convoy escort command game. And that would require a slightly different approach.
That said, commanding a convoy or convoy escort rather than just a destroyer could make for an excellent and unique tactical wargame.
Actually, here is a proposal:
Make an SHIII-engine based game where you could command small attack boat groups, convoy escorts, hunting/support groups, or even big battle groups. You'd be the squadron commander sitting on one of the ships, and issuing orders to not one, but a whole number of units. You'd have both an SHIII-style nav map with waypoints, and radio menus to automatically make them execute manuevers and such. If needed, you could also take direct control of your boat a-la SHIII, and fire some cannons and torpedoes by hand or something.
Now THAT would be a much cooler approach.