You called me Tonto?
Anyway I think valinor could very well be america before it was invaded by "man". If that is so then Numenor's destruction would be a maybe even greater metaphorical plot device to symbolise his disapproval of how the europeans treated that land and it's people. He hated machines and loved nature, if one would draw paralells between the fictional and real world which Tolkien did. Then I think in fact that Valinor could represent america before the cowboys invaded it.
Drowning Numenor and moving valinor from the world would then be quite significant and very interesting. Also if one assumes Valinor to be america before it was invaded by the europeans then that would maybe help one explain some enigmas in the story that aren't thoroughly explained. Oh yeah and if you calling me Tonto was meant as an insult you're quite off your target since I'm scandinavian.