All good points here - I would only add one thing: when I did my first startup right out of college, we were constantly worried about what our "local" competito

All good points here - I would only add one thing: when I did my first startup right out of college, we were constantly worried about what our "local" competitors were doing - meaning companies targeting the same market and about the same size. What we ignored, and hurt us, was the larger company entering the space. Moral of the story: focus on your start-up vs. looking at local competitors, but keep an eye on larger companies that have the potential to come into the space.