Echo the same responses everyone has said -- my depression is much better now, four months sober, than it EVER was when I was drinking. It's not gone, but it's much more manageable. I'm not suicidal and unable to get out of bed, like I was before.
Also, getting sober has revealed some other mental health issues that I can now deal with that I didn't even realize I was self medicating for.
Good luck to you, you have a great plan! It will be hard to stick to it, but I know you can do it!