Seems like overkill for our use case but idk, so I'm looking for opinions before my first espresso machine arrives. We don't have the most refined palates compared to what some espresso enthusiasts can distinguish, so I really only took an interest in this subject when I heard about scale-free water systems as a way to extend the lifespan of an espresso machine.

Machine is an Argos spring lever. We have a CuZn UC-200 filter installed on the cold water line under our kitchen sink, which results in water that tastes great to us. Our household will average something like 4 double shots per day, mostly lattes. Local water authority reports water is considered soft (<=17.1mg/L):

hardness: 16.7-17.1
calcium: 4.8-4.9
magnesium: 1.16-1.19
Total Alkalinity: 22
Bicarbonate Alkalinity: 22
https://docs.pcwa.net/ccr/foothill-sunset

That's very soft water, seems typical for northern Sierra Nevada mountain surface waters. The report indicates reasonably low chloride so I don't see a corrosion concern, and your UC-200 is a good choice for filtration. You might see recommendations that it's too soft for ideal taste reasons, but I think you can ignore that. There's plenty of mineral for water sensors to work if you were ever to get a machine that has that, and you'll probably never need to descale.