How to turn my web application into a lifestyle business?
pedalpete: First off, that site is amazing in it's simplicity. Even your sign-up process is the easiest I've seen (though I'd make it more clear that it is a sign-up, because I wasn't sure if I was supposed to already have an account).As far as monetizing, with the volume of todo lists available, you may have difficulty monetizing in such a direct way as getting users to pay monthly.You mention Covey, and clearly you are influenced by his work. Have you considered contacting them and seeing if they'd be interested in partnering with you?They could use your services to build their brand online, and help with defining new features, while you do what you do (which we can see you do very well).The Covey site (https://www.stephencovey.com/) mentions that they have online tools, but maybe your stuff is better, and maybe you could sell them on it. 
Or other competitors who are in a similar market.