The kinds of analysis I have played with the most with Sense export (CSV) are:
Look for Missing Data, especially in the mains (Usage) and solar (Solar Production). Those are a good indicator of general internet and Sense reliability.
If it looks like the mains and solar data is all there, compute and compare the net usage from Sense against the net usage from my PG&E utility net meter. The link below shows what these first two look like:
Then it’s useful to look at usage and changes in usage by device category, or the top 10 individual devices.
Finally I like to look at correlation between my Sense air conditioner (AC) detections and the AC runtimes coming from my upstairs and downstairs Ecobees.
I’m going to try to repeat this kind of analysis using Perplexity Pro. The main caveat is that I typically do my analysis on a yearly basis, but the 25MB file size limit of Perplexity Pro will likely keep me limited to monthly datasets.
ps: pretty impressive that you have the SDR up and running for water flow. I broke down when the local water companies started offering rebates and bought a couple of Flumes, which do similar. Had some fun trying to correlate them against my Rachio sprinkler runtimes here.