My ideas below is not well thought out, I made them just to get a brainstorm going, to get other to find new ideas.
But there is one thing I like about sh2, the menu and game music. It fits so much better for sub simulation. If they can step just a few inches back (doesnt have to go all the way back) but at least mix up a little bit of sh2 music with modern music. Btw. I have the original sh2 here, its even in a box, you don't find many boxed games anymore in the stores, I like the box. I also have Destroyer Command (Original)