The perfect email
Original email writer here.
I generally agree with the comments about how it could have been improved.  In hindsight, it was probably too wordy.  My impression is that David processes emails more "deeply" than the average person, so I think he could handle the wordiness.  Others would probably trash it more quickly.
I did get a very thoughtful response from David which actually helped us immensely.  As a result of taking the path he suggested we've now got a great business going, and the main problem is hanging on to the rocketship it has become.  Obviously, a high-class problem to have.It took me a couple of hours to write the email.  Definitely time well spent.