British English has idioms and figurative language use - just like all versions of English. The fact that you think it is "redundant" or "strange" is because you presumably speak a different language. It doesn't make either language "wrong" or "incorrect" - despite your prejudiced implications.
To address your specific questions:
"In the move, "A Night to Remember (1958)," the second class couple, before leaving England, promises to send their relatives a wireless "from the ship." Just where else would they send it from? "
Firstly - they wouldn't have sent a wireless - that's an actual radio receiver. I suspect you mean a telegram (also called a Macronigram in this era). They could have sent it from Cherbourg where Titanic called before heading to New York; they could have sent it from New York when they arrived. You also need to remember that the ability to send telegrams from a ship was still a new and novel experience - so emphasising or clarifying the fact would be commonplace.
 A crew member who spotted the Californian exclaimed that it was so many "miles" away, with heavy emphasis on the word "miles." Was there some uncertainty about the measure of distance?
The miles was indeed to emphasise that the distance was further than would be ideal. It is also necessary to clarify that he WAS specifying distance; and not time.
For example "The ship is two miles away" and "The ship is two hours away" are both valid English. Saying "The ship is two away." is both ungrammatical and needlessly ambiguous. More generally, it always good practice to specify the unit when providing a numerical quantity - especially in a shipboard context, where many different units were in use (miles, yards, feet, fathoms, leagues, cables etc).
Another crew member assured someone that the Carpathia should be here "any time now," which emphasis on the word "now." What does the word "now" add to the sentence?
"Any time" means it could be literally time, in an hour, a week, a month - three centuries etc.
"Any time now" means that the event is imminent and expected very soon.
In other contexts, the British will preface an assertion with "in actual fact." If a "fact" is not "actual" (i.e. true), then it is not a fact.
Using redundancy for emphasis is again common in all English languages. For example why do Americans say "real estate agent"? To differentiate it from a "fictional estate agent"(?)
The British refer to an ordinary flashlight as a torch. What do they call a real torch?
We call it a torch. If any disambiguation is necessary (which is very rarely) then you could clarify with "battery torch", "burning torch" etc.