This is great! Thank you for what would seem to be a major piece of work.
The only issue I had was the extra loud sound of that diesel engine.
I found out that it is only loud if you visit the engine room and come out of it. It could be a mistake but after about a half hour I went below again to the control room and it was again reasonable.
I have only just started out in career mode, about 50 km out, but so far all is well.
Again, nice job! SH3 has now pushed ahead of SH4 and might even be better than SH5. But SH5 is another story...