I am all about slower as well... That's the difference between a deep cure and just a basic cure. You have to leave a little bit of moisture in there to get this, but the majority of water is just excess and unnecessary.
I don't have any tools or instruments to tell you the exact amount of moisture, but I do have a whole lot of experience.
One thing you will notice more than anything if you come out to Colorado and spend a bit of time with cannabis is that the shelf life is about 3-6 months depending on your curing skills. I can't tell you how much great bud has gone to the wayside because people rush things to make money. In cali, the most beat up outdoor will still stank harder than a lot of dried out indoor in Colorado. Humidity is very conductive to terpenes. Back in Louisiana, a 1/4oz of bud would stink up a city block, here in colorado, some top notch OG will barely stink up your car....