Samsung will shut down the v1 SmartThings hub this month

So there are a lot of negatives to trying to set up your home as a smart home, the constant fight against entropy is the most annoying. These kind of service shutdowns are way to common.

If you are just getting into it you should ironically try to get smart devices that are as dumb as possible (or flashable to be) and do all the thinking and control on the hub.

For the hub it's worth looking at openhab or home assistant and running it on your own hardware.

I definitely enjoy the benefit of having everything be voice controlled. To stay offline you can use mycroft ai though will require a bit of set up to work like that. The utility of having a voice assistant connected to the internet is pretty great though so might outweigh any privacy/security concerns either leaving mycroft connected or using amazon/google/apple options.

Follow that advice and you can have a stable functional smart home. I wouldn't call it a consumer friendly experience, though if you look at it as a tech hobby there's a good helpful community and you can definitely end up with a pretty awesome environment set up.