Looking more I will have monitoring with the daly app. what I am short of is as you say " getting the BMS info out into the wider world." Until someone hacks the Daly BMS!
Despite its cost the only way to get automatic action seems to be the victron bmv 712 with its programmable relay, with added Ve direct to usb. Is the RPi just for setup of the bmv and better monitoring than the little bmv screen
Look at Node-Red you can read ALL VE.Direct data from Victron devices and then control relays.
Node-Red is a graphical programming language so little code writing necessary.
List what you think you want to do.