If you're doing well freelancing then have you considered doing something to generate passive income? It might not sound great, but a popular wordpress/drupal plugin could bootstrap a business, and a range of semi-popular paid plugins could be a business.
I know your concerns are mainly technical, but you've given us no idea of the type of business you're looking at starting. If your business idea is good enough and you think you can deliver then yes, I'd say go for it. As a single founder though I'd like to warn you that no matter how successful (or not) you get, it'll suck the life out of you like a vampire, so make sure it's something you're going to enjoy beforehand.
I've got a whole notebook of ideas, but in particular, I've been working on some studio management software for my own piano studio. The market wouldn't be very large, but turning it into a web app wouldn't be very difficult.
I'm a competent programmer, it's just the auxiliary skills that are really lacking...
I know your concerns are mainly technical, but you've given us no idea of the type of business you're looking at starting. If your business idea is good enough and you think you can deliver then yes, I'd say go for it. As a single founder though I'd like to warn you that no matter how successful (or not) you get, it'll suck the life out of you like a vampire, so make sure it's something you're going to enjoy beforehand.