Personally I'd stay at the job until your projects get some actual momentum. Leaving your job to work on your project is really exciting at first but it can be pretty disastrous if you don't have a 'plan b'
Financial stress while doing startups is very distracting and possibly deadly to the new company. Plus your income can help fund expected and unexpected expenditures.
I've done 8 startups, only one from my savings. I'm on #8 right now with a job and slowly building it on the side. It's 12-16 hour days sometimes but I have health insurance covered, paid time off/holidays, and significantly more revenue than I need with dual incomes.
I'm leaving once there's enough capital in the company to cover myself and my partner's payments for 1 year with no income and our first 5 clients.
If you feel you're not giving your customers the service they need, you can setup a small coloc office and hire a 15-20/hr employee to man the phones give customer support.
Good luck. I worked on AR products in Oil & Gas, some of the worst crap I've ever seen in my life. A good workflow will make your users love your product, so eat your own dogfood :-)
The groundwork your laying now will help determine whether you're successful down the road.
Read The E-Myth on how to run a successful business. It's a bit silly in its writing but the point of the book is really helpful and eye opening in my opinion. I've got my startup partner reading it now. He's 100% the "technician". It's only 280 pages so maybe a 2 day read max.
The best sales book I've ever read is 10 Steps to Sales Success by Tim Breithaupt. I think it's out of print but you can get a used copy cheapo.
Running a business is a hell of a lot more than just coding, the sooner you recognize that the better your chances to succeed.