The "whoever finishes the book first picks the next one" rule is lowkey genius because it turns the boring part into a race. Bet your meetings got more fun too since people actually want to finish now.

I'd slow down before calling the crawl space the next problem. Air sealing matters way more than people admit, and if your attic hatch and can lights are still leaky, that new cellulose is doing half its job. I paid $400 for a blower door test in Marietta and it showed 3,200 CFM of leakage, most of it from the attic floor and a dead flex duct in the crawl. Fixing that leak cost me less than another round of insulation and dropped my bill another $30. Get the test first, then spend.

Check the meter lid first, that's solid advice. But how did you know to look at the valve versus the seal around the box itself? I had a similar thing happen where the hissing was coming from the meter body gasket and not the shutoff, and I wasted a whole weekend tightening stuff that wasn't the problem. Was the drip pretty obvious once you got down there with the flashlight, or did you have to feel around for moisture? Also curious if your water company ever gave you a credit back for the spike, because mine basically told me tough luck when I tried.