Welcome
, these are a few suggestions.
In the end though, it will be trying them and deciding for yourself.
Patrol Mod - New starting locations/patrol enhancements
Smaller Seabed Rocks
There is one for smaller plants as well, could not locate it.
Slower Smoke
Pull Down Pacific Map
Sky Environment Mod v1.0
Battle stations & Silent Running on all HUD stations
Changed HUD Lamp Color - Green for depressed buttons
Ultimate Soundmod
"Ahead 2/3" Sound Mod + Missing "Crash Dive" Voices
Captain Midnight's CBS News Mod
Smaller Plants
Texture mods ( skins for the sub ), there are various ones, pick a few and try.
Add some period pieces to your Grammaphone and this should get you started. The radio mod link is an excellent one.
Get used to installing and uninstalling mods, once you start it takes awhile to get things molded to your preference. Use the mod enabler JSGME, it it will make your life easier:
http://forums.totalwar.org/vb/showthread.php?p=1009484This an illustrated guide
, the enabler itself is located I think at the top of the mods page as a d\l.
Trigger Maru and Real Fleet Boat are some bigger compliations, have a look at the read-me's for each.
This list is a little old, there are to many to name, plus there have been some new ones added recently, again have a look.
Folks here have done some great work
Good Hunting
RDP