Good luck, Alex,
Those are darn fine goals if you ask me. Work your passion. Nothing else in your working life will make you as happy. As is evidenced by the LJ's site, there are customers out there who cherish fine craftsmanship, they're just hard to find. And they will almost always ask for a bargain. I have found that a few really great customers, (who many times become friends) will help you through the 'thin' parts. I have been given commissions when it was really slow with no real time limit, but a value that we could both live with. I doubt many of us will get rich. Mostly, if you're lucky, you make enough to pay the electric bill and keep food on the table.
I once read an interview with James Krenov, (years and years ago, but he was already very well known in woodworking). In that article he states (paraphrase here, like I said, it's been years) "If my wife didn't work I couldn't do this." In the pictures was dressed in a flannel shirt, couple days beard, like a guy you'd run into down at the lumber store.
I have no idea what his personal wealth was, but I seriously doubt he got rich doing what I think was the best woodworking and cabinet building I ever saw. I think Sam Maloof did better marketing, tho.
For me the fortune is in the creative flow, the process, from idea to holding it in your hand. I don't know about specialization or niche or categories; I pretty much make what the customer wants. Occasionally someone will give you the chance to make something with a slight element of originality, vision, or art that no one else is doing. You can see thousands here on LJ's. You'll probably lose money on that, but for me, those were the most enjoyable and memorable times.
If you're fortunate, you will get thru 30, 40, or 50 years and the things you designed, created, and crafted will be a 'body of work'.
Some advice, sign or brand everything you can. Some things can't be. Many of the pieces you build will bring in other customers. Hold down your debt. That's what eats you.
Don't get discouraged, have fun, force yourself to take a vacation once in a while (we never made it to 'annual vacation').
Trust in your own vision, but don't hesitate to give the customer what he wants. If you are diligent and persistent, you will build a reputation and a business.