From a beer perspective - others can comment re appropriateness to wine making - Using a spunding valve, ferment under pressure. For beer I usually set the valve to about 10 psi - I'd think wine would be less. Ferment under pressure carbonates naturally & with the yeast gobbling any O2, it's a pure CO2 environment in the fermenter.
Remember, everything needs to be chilled to prevent foaming.
When ferment is complete, using a floating tube with filter to transfer to a CO2-purged keg, I set input pressure to about 13 psi so there's 3 psi pushing the liquid.
Using the PRV & watching for any slow down of transfer to indicate when to release pressure in the keg I fill to 19kg - I have the keg sitting on scales good to 40kg - empty keg on, press tare then wait for 19 kg.
For wine I would then disconnect, release some pressure & connect it to serving pressure CO2 in the fridge.
I would guesstimate it might need maybe 5 psi for serving as I wouldn't want to push it out hard enough to create a beer-level head in the glass - start low & increase as needed rather than having to degas if it's too high.
If you then want to bottle, a counter-pressure transfer system works great & most taps have connectors that screw into the tap on the kegerator. e.g. I use Nukataps & have a specific CP connection for those.
