Can anybody give advice for making my older Astoria 2-group commercial lever machine a bit quieter?

This is my machine:
Rebuilding an old 2 group Astoria Lever (+ propane)

Right now the lowest thing in the house at 7am is this thing filling water and pressure cycling. Can I reduce the water fill noise of the solenoid? Can I replace the pressure stat relay with an SSR?

I've placed the coffee grinder in the garage but I don't have plumbed water or waste water in the garage. This beast lives on my bar island and there is some disagreement in the family about sleep (for non-espresso-drinkers) and espresso (for me). If it was quieter then I could have my espresso earlier.

You can line the inside sides of the case with sound deadening insulation - I've used closed-cell Silicone foam/sponge on my machines because I had a bunch lying around, but there are many alternatives.

For the pressurestat, yes. However, a more common(?) approach is installing a PID to control the SSR, and then raise the pressurestat a little bit so the pressurestat acts as a backup in case of PID or SSR failure.

Installing a PID with SSR and leaving the pressure stat in place is a great idea! What is everyone's preferred simple, and fool proof PID these days?

A comment about PIDs for this purpose and another option.

A standard PID that most machines use is one that uses a thermocouple or other temperature sensor. Because steam temperature in a boiler is linear with pressure, this works for our purpose.

There are pressure transducers that directly measure pressure and dedicated pressure PID controllers that are designed to use that type of transducer. PM me if you want details on the one I just used for my lever build.