For me, it would end up being more expensive.
For $35/month, I get unlimited talk text and 5GB of data. This is grandfathered from VirginMobile (sprint/boost). There are no overages. If I exceed 5GB, then the speed drops. Comcast wants $12 for each GB. If you don't use much, you save but go over 2GB and it would cost me $36. That's more than I currently pay and for less data.
I also know VirginMobile has great coverage on the East coast. I've been with them since about 2006 and the only place I had no cellphone coverage was in Bar Harbor Maine. That was in 2009. They probably have coverage there now. (I had a phone with only cell service, no wifi ability).
You can also use the Xfinity hot spots and you home WIFI and save on you data pan.
Thought you had just gotten new phones with Verizon? If you did make sure there is no ETF (early termination fee) since some times getting a new phone through some carriers will extend your contract. Plus you will have to return the newly purchased phones if they were purchased through Verizon.