I figure it goes to '43 and has VIIs only because it's a perfect segue into expansion packs. Different operations; eg. get the Type IXs with the Paukenslag expansion. Many, many, possiblities.
The original SH had 3 or 4 expansions, mostly maps if I recall.
If they do a good job detailing the individual types (performance, charecteristics, etc.), it could be a very good thing.
They simply must eliminate the bugs that were still present in SH4 from 3, and prevent the addition of new/old ones like the reversed engine sounds in Uboat missions.
I would not like significant changes to the campaign. Incorporate more refined and specific mission objectives, but leave the sandbox in. What I envision is something along the lines of a real mission, including orders from BdU specific to your boat, mission, and wolfpacks. Unknowns/random events like being blown off course due to weather resulting in a failure to meet up with other boats at the proper time and coordinates. (ya I can dream
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