Where's the Chief when you need him ?
Just to answer some of those left (have not played the game since the GWX3.0 release) :
- Community_units
adds a number of cargos IIRC
- Flying Dutchman
Erm... 
and all that, ya know. Okay, it's a ghost ship.
- GWX2.0_Moon
adds a new resized moon reworked by the great Ichneumon.
- liferaft_1 and _2
a mod made by the pretty skilled Privateer and Thunder, featuring crew leaving their ship when the unit is destroyed. Thunder did the animation work, Privateer took care of the inclusion in the game.
- NKSs_T05.tga
new texture for the small merchant
- Real Depth Charge
new depth charge sound
- Turm_7B_Historic
Tarjak's work IIRC,
pack of new - neat-looking 
- emblems that were used in real life.
- Turm_VIIC_1_Historic
ditto
- Unmark
? I think it removes the orange mark on top of your boot when you're underwater.
- Wac Animated Sub Pens
Hansolo's work, this cool guy created new U-Boote bunkers featuring new objects in them.