Nos. 2 and 7 are prohibited by the Rules. Strobes are for emergencies only and a spotlight in the eyes would earn the scorn of mariners and possibly a citation from authorities.
No. 1 is mandatory for operating a vessel between sunset and sunrise
No. 3 can be helpful in some situations
No. 4 is a good thing to have
No. 5 is normally used only in SAR situations
No. 6 is expensive but very good thing for small boats to have when in company of large ships or fast moving ferries, especially in situations of reduced visibility.
I recommend you read Part C of Navigation Rules Online
Ah, for that matter, read the whole thing!