PrivatePilot,
I am not saying that you claim it is NW's fault. In fact, a couple of times I said that "it sounds like......but I'm not saying that's what happened". The reason I did that is mainly because of your third point:
Originally Posted by PrivatePilot
3. Any other ideas?? (Great Potential New Customer, already spent over $1000 on his first three flights in 3 months, etc. will continue to fly more.. don't disappoint new customer, etc)
Absolutely, go ahead and write and state your case but when you say (threaten?) things like "will continue to fly more", it sounds like if they don't acquiesce to your request, you won't fly them anymore.
What about everyone else that opened a WP account in April? Should they also be given the additional miles? How about accounts opened in March, February, etc? Where do you draw the line?
There really is nothing unique or special about your circumstance that would warrant NW making an exception. I think if you are going to write, you should just be straightforward with NW and ask if there is any way possible to get the additional miles. I wouldn't try to add in all the fancy stuff as it just makes it seem that you think you can pull the wool over their eyes. I'm not saying you are, it will just seem that way.
I know I am much more likely to make an exception for a customer if they just state the facts in a case like this. When I see that they are trying to pass the blame (and to some extent, be deceitful), I can no longer believe anything they say, including things like "I will continue to use you if you do this for me".
Bottom line is that it never hurts to ask, just don't expect anything and don't hold it against NW when you get nothing.