Voted these 4 as my preferences, in order of eagerness:
7) Playing with naval surface ships - campaign against the Axis
8) Playing with naval surface ships - campaign against the Allies
1) More types of uboats, including midget submarines.
2) Campaign to the end of war: 'Last years' 43-45
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7) Definitely the Multiplayer-mode saviour that would boost online play (because let's face it, the current MP mode is obsolete... coop mode doesn't always end the need for fun with your buddies). An adversarial mode that has fully playable subs fight fully playable surface ships (DDs and DEs are preferred, though I wouldn't mind all kinds of ships) would revive the spirit of online play in subsims. An SP mode (or the possibility to design missions and campaigns for it) would also be nice, as not all battles are held in the same environment (be it SP, or MP).
8) Playing with axis naval surface ships sounds like some fun, and, in the abscense of an allied ships sim, would give the oportunity fill the gap anyways in the form of mods, as long as there was the possibility of interoperability with the sub games.
1) Maybe I'm not too thrilled about midgets, though I'd definitely like to see at least Types II and IX modeled in.
2) Not really a priority because maybe it's a relatively easy thing to mod in, but it would be nice if the modders didn't have to make so much stuff for people to feel the sim is complete. We've already shown that we don't mind delays, so long as they have a purpose.
Cheers