I'm not a phone case type of person. I have an older Note 4 that I purchased brand new, and the ONLY time it was ever in a case was when I was on vacation and I wanted a water proof case to use it in the ocean. That said, the glass back of the Note 8 is VERY slippery. I've dropped it twice onto my carpeted floor, thankfully, because of how slippery it is. So I picked up a minimalist case from Spigen that's the same gray color as my phone, so I don't really feel like I'm using a case at all. It doesn't really protect the phone at all except gives it a slight texture non slippery back for me to hold on to. Aside from that, there is a tiny bezel across the top and the bottom. If the phone falls screen down, this should assist in the screen not hitting the floor and breaking.
What's also nice about the case is it has a space to stick an adhesive metal plate in there. Now it easily holds onto my magnetic car phone holder that sticks into the AC vent. Also Spigen.
Here's the case -
https://www.amazon.com/gp/product/B073R7588V/
Here's the magnetic holder -
https://www.amazon.com/gp/product/B01AMGFY5M/
I like how small this holder is. It doesn't look horrible when not being used the way other holders do. And it comes with a bunch of metal plates.
EDIT: The ONLY down side at all to having a case/metal plate is it makes the charging pad unusable. I have the pad at home, so when I get home, I pop the case off and use the pad. No problem there. It's just an extra step.