New to backpacking, how does all of my gear stack up?

Your stove has a piezo ignition. They are notorious for wearing out and failing.

You could substitute a mini-Bic lighter for the firesteel and it will light your stove if the piezo fails. I've never lit a stove with a firesteel, so maybe it would work. At any rate, a mini-Bic is really light and super dependable.

I hope you packed that .357 legally, these days LEO have no sense of humor. You may now that but I'd hate for you to get in trouble.

The other commencements I agree with. If you're already committed to the boots you might as well wear them out but I don't feel they are needed. I made a cheap tarp which weighs about 8 oz. Combine that with a MYOG bivy and you have a lighter shelter for $80 or so worth of materials.

Edit – Your pack is a bit heavy but don't replace it yet. If its comfortable keep it while you change other gear. Once your other gear is lighter you can think about what new pack (if any) is the best fit for your new gearlist.

BOOTS> Keep the Merrill Moab GTX boots. (I have 'em and love'em.)
Buy the Merril Moab Ventilator shoes W/O GTX for times when you're SURE of no rain or snow.

Tent> Look closely at the Tarptent Notch and Moment solo tents. I love my Moment.
Great quality, very fair price & made in USA.