I previously used a Galaxy S3 with Replicant OS. I also have a Sony phone with Lineage OS (with no Google). I now use a dumbphone as I don't particularly like smartphones. This decision is less driven by security and more a desire to ringfence time away from tech.
Personally, I was never bothered by the lack of GPS. I'm fine with offline maps. I have a satnav in the car which is the only time I really need minute-by-minute navigation.
I found the lack of WiFi to be a bigger issue. Mostly as I like podcasts. There is/was an option to use a WiFi adapter which works well if you plan in advance (i.e. use it when downloading a bunch of apps when setting up, or downloading a bunch of podcasts in one go).
Replicant OS is a really neat project, and they deserve some praise.
