Congrats. That is a lot of work to make it into what you wanted, though.
I'd have been pissed at the different tire and valve specs; it's a bait & switch!
I've always liked the idea of a single speed bike, but in practice, I want at least 3 speeds. You can still get that in an internal geared hub. 5 are more common now.
I plan to ride my old Trek comfort bike most of this winter about 50 miles north of you. (Kenosha)