Nice. I think stoners and hoarders go hand in hand, especially with containers
I have a stack of the little hygrometers and I never use them. They have an acceptable fluctuation of 5% which can be enough to make a difference.
As far as the containers, I'd give it a squeeze when it's closed to see how air-tight it is. Probably perfect for curing since air exchange (burping) is needed anyway, but I dont know about long term storage. A bunch of those in a gamma-lid bucket or something else hermetically sealed would fix any of those issues.