About the dark interiors, you can use the Rusted Glory mod, "only lights" variant.
Improvements for see: How to match the awards (historical way) of KSD and TWoS. In SH5 is very hard to obtain an award.
Possibility to add more merchants types - for example, from SH4 FOTRSU, to the roster of TWoS.
Type IX boat
Regards.
Fitzcarraldo