I decided to try Google Fi, their wireless phone service. At the same time, I purchased a new phone for Wife since her phone is ancient with horrible battery life, and wasn't fully compatible with Fi. The new phone was a Moto G Power, a mid-grade phone with excellent battery life. The phone was advertised as carrier unlocked so if Fi service didn't work, I should be able to use it on Verizon.
Apparently two phone lines require two Gmail accounts and I was supposed to sign up for Fi, then invite Wife. I tried to set her phone up first, which linked it to my account making it difficult to switch that to her phone. I also didn't want to completely leave Verizon until at least one phone was working on Fi. After several hours with support over several days, Support wanted me to abandon my phone numbers and get new ones. Finally got it mostly working except with Wife's appointments showing up on my phone.
Unfortunately coverage wasn't very good at work or while commuting. After giving it a few months, I decided to go back to Verizon. My computer is Linux. Verizon's website is virtually unusable with either Chrome or Firefox on Linux.
It turns out that the "unlocked" Fi phone isn't fully unlocked--the Google Fi software only allows phone calls on Verizon's network but does not allow data. This caused hours of support with Verizon--got the phone working by switching sim cards from phone to phone, we assumed that data would eventually show up. It didn't. The phone could do calling and texting, could not send a picture via text, and anything Internet was wifi only. I finally did some research and found that this is a known issue with the Google Fi version of this particular phone--Google's software won't let the phone connect data to Verizon's network. The software can't be changed without voiding the phone's warranty. Google offered to exchange phones with an identical phone with identical software. I questioned that, since if the software is the issue the problem is likely to remain. They persisted, I asked if there were other steps to take if the same software caused the same results, they assured me that there was. The new phone arrived, exact same results and it turns out that the "other steps" was "ask the guy at the next desk".
I finally unlocked the phone, voiding the warranty and installed Verizon software. The phone works perfectly--pretty much proving that the problem is neither hardware nor Verizon.