One thing that rubs me wrong with HN is a general feeling it creates in my gut that my projects isn't valid because It's taken us 5 years to get stable. I feel like the pattern is to take a bunch of people's money, blow through it and then quit when your idea didn't work in 6 months. Then repeat. No point in sticking with something unless it's an instant smash hit.
Steve, I think your idea is pretty solid and there surely must be customers out there like schools that will add large numbers of accounts. If you can build it to where you can sit on the beach doing support then what a great life that could be! All the best to you.