I live in Michigan too. Have you tried Visible, Verizon’s discount carrier? It works great for me in Greater Detroit region, the thumb, and up north. I pay $25/mo for unlimited everything.
I used to use a tier 2 carrier. Then we had the freeze / grid anomaly in Texas and it resulted in a lot of cell phone traffic. My wife who was on a direct plan with ATT was able to use her phone most of the time with little issue. Meanwhile I was on a tier 2 carrier and had nothing the entire time. Work's great until it doesn't.
I have a friend on the police/emergency responder ATT network (FirstNet) and he said he's NEVER had it slow down since those EIMIs get priority routing. I'm sure someone in telco network operations could explain this even better than I can.
with "unlimited data" that is capped at 15g. unfortunately it's the only provider that works where we live in Michigan