Good to see someone else actually doing tests and making measurements!
I suggest you try a flight mode test to eliminate the drain of the various radio signals - as these very much depend on how close you are to the cell site, and wifi.
From your graphs I calculate 1.2%/hr discharge rate.
My own reported results in flight mode was 0.7%/hr.
It can be calculated from this that more than half the power is wasted in idle doing nothing.
Or to put it another way, if the idle current was reasonable (what it is in Android), then DrDweebs phone would run for a week like this instead of ~3 days as it is.
This also likely shows that the current drain to keep the radios running is not too bad, the excess idle drain is what is killing it.