pool-controller.js (GitHub - tagyoureit/nodejs-poolController: An application to control pool equipment from various manufacturers.) is an application that connects in to a Pentair system directly via the RS485 bus, and gives you MUCH more detailed control; and visibility than the normal pentair integration does. This includes pump speed controls and a whole host of scheduling and other capabilities.
It’s also easily interfaced to HA via a HACS integration here: nodejs-PoolController Integration
I run it on a separate raspberry Pi that is close to the pool equipment, but I guess you could try and run it on the same computer you run HA on. It will be easier if its split out of course.
That should give you the level of control you are looking for.