Unless you are playing Oct 44 onwards you dont need the late war sensors enabled yet
Unless you are using a VIIC\41 you dont need that enabled
Alternative flotillas just gives you the 3rd flot at La Pallice so unless you plan on being in the 3rd no point in enabling
Lite Harbour traffic is for PCs at the low end that struggle in home ports
Black Sea files ONLY if you are playing in the Black Sea
Indian Ocean files ONLY if you are playing in the Indian Ocean
Merged Campaign INCLUDES the Indian Ocean AND Black Sea campaign files - hence MERGED
All the campaign files overwrote each other so only the last one worked anyway
If you are playing in the Atlantic\Med\Baltic\Arctic then you dont need to enable any of the campaign mods unless you need the lite harbour one