Hi Erik, Sounds like we ended up working on the same issue at about the same time.
Great to hear you have a basic path forwards. I am very much a fan of the open source ModularSensors and EnviroDIY which covers a lot of functionality.
However, it is a matrix of south bound (away from internet) instrument sensor interfaces ~~which are fantastic~~ and north bound (towards internet) communication interfaces.
I personally have just a few configurations that I’m trying to build for the future, very much with RS485/12V (and SDI12/5V as instruments support it).
From the software engineering aspect of the open source, there is no regression defined. So I’m attempting a definition of that.
SO interested how it works for you.