I guess depends on a lot of things
I personally believe if DLC is the way Ubi want to go you will see a Pacific addon for SH5
Files are still split into American and German as was SH4 - that maybe as most of the SH3 and 4 files are still ingame including all the US sub textures
That way users HAVE to buy SH5 before the addon
Double your money
No discs to produce etc

Have no doubt there will be another Pacific instalment
Unless they drop SH like a hot potato after the fiasco that was SH5 on release

We joked about an official approval 'stamp' awhile back.
Find that thread if you want to see some major whineing!

I am not a GWX team member. But through the years (5 now!) I FEEL part of this GW family. The continuation of the legasy (GWX3.1, 4.0, 5,0 you name it) it will be something bigger than Xpansion; it will be a great stand against the online-based DRM of Ubisoft's SH5 and the systematic "arcadeness" of everything around. Maybe I am a romantic freak but... I love this game!:salute:

Despite the obvious improvements and glaring removals
Not to mention the huge potential of SH5 I still have SH3 GWX installed and regulary take my type 9 out for a patrol

Not just nostalgia either
Has a grittier feel
More immersive

If one is serious about simulations SH 3 modded is the closest you can get to the Battle of the Atlantic.
The rpg element is the only thing SH 5 seems to have going for it, even that seems unfinished.