I think you've got some good ideas
A KB is good in that it can provide lots of information, but, it relies on a customer looking at it rather than them simply firing an email off.
Presuming you work 9-5, and sleep 11-6, you should be able to offer <12 hour responses without any problems. Hire a cheap ($30/mo) server administration company (such as PSM -
www.platinumservermanagement.com) to monitor and look after things if it all goes wrong in the middle of the night/when you're at work, and then couple that with an 'emergency' address that goes to your cell/pager and everything should be under control

If something goes wrong, customers can contact you without you having to actively check for any issues (you can then look at the issue during a lunch/break or get out of bed), but, PSM's monitoring should have picked up the issue and they get on to fixing it/rebooting the server.
When you've got the cash flow and customers, both BobCares and Touchsupport offer ticket based support for around and under $100 per month.
http://touchsupport.com/outsourced-t...rt-support.php and
http://bobcares.com/page-20-16.html. Both companies have pretty good reputations
