Welcome back guys:
My must have list looks like this below.

but such things are a matter of taste. Best you collect things you like and put them all into one folder. So you can easily create new EAW installs for other campaigns for instance. An absolute must have are the new exe files (by me

)
I forgot: the links to all add ons listed below can be found on Sandbaggers EAW LInks page. Simply check any of Sandbaggers post and have a look to his signature to find the link.
HiRes Airfield Kit (Ghostboy)
HiRes Ground Objects and Targets (Ghostboy)
HiRes Train Set (Ghostboy)
HiRes Flak Pack (Ghostboy)
HiRes Destroyer grey TMOD72 (Ghostboy)
HiRes Transport Ship TMOD57 (Ghostboy)
Opel Blitz TMOD53 (Geo)
Kübelwagen TMOD54 (Pobs)
EAW People (Max188)
HiRes Railway lines Summer (Col. Gibbon)
Summer Trees (von Oben)
Matilda Mk II TMOD56 (Pobs) (for early campaigns only)
Panzer III TMOD55 (Pobs) (for early campaigns only)
ReviC/12D (Luftwaffe) (Nibiek)
Effects Pack (Fire & Smoke) 31/08/01 (Max188)
LW drop tank 1.0 (Mosi)
Realistic EAW Hills (von Oben)
HiRes Parachutist (?)
Inflight map with names (JWC)
Euro-Blend Terrain v1.0 (SagginB)
Overcast Sky 1.0 (Max188)
my eaw.ini
Officer Ranks LW (Andy)
eaw12c.exe
Sounds
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chute sound
20mm Cannon (JS)
50 cal (JS)
303 cal (JS)
Serbs sounds except above listed