Applications going through Buffalo are generally much quicker outland than they are inland, plus you will have the right to appeal if you are denied, and you can travel to and from Canada during the application process. In most cases, outland is the better option.
Anything you don't include in the first stage of the application will cause you delays later on. It's best to put it all in the application up front and not have to worry about it later.

The process is long and stressful enough without adding complications and delays.