I've finally got a setup/case combo that meets my needs. At least for now. While I really didn't mind having to use adhesive strips at first, having to frequently reapply the strips when changing cases has become a pain. I'm now using the Kevlar/aramid case from Latercase and Speck's clear one piece Presidio case. Neither case requires adhesive (Latercase uses a grippy rubber-like strip to hold the front cover in place and Speck's case is a single piece, avoiding the necessity for adhesive or any type of grip altogether). Not having to reapply adhesive makes swapping between cases a breeze.
As most of you know, the case from Latercase is minimalist in design, but offers solid scratch/scuff protection. The Speck Presidio looks and feels great, but it's pretty bulky and quite a bit heavier. I use the Latercase case most of the time, because it's slim and lightweight. I slap on the Speck case when I know I'm going to be out in conditions or situations where there's a greater chance of dropping or damaging my Fold3 (outdoor activities, out drinking, etc). For me, this combo is pretty much perfect.
I also have an AI Autofocus case with an integrated screen protector and an S Pen slot built into the hinge protector. The AI Autofocus case is very bulky, inconvenient, and hideous but it also doesn't require adhesive, and it's useful for situations in which I need hinge protection and better protection from dust and dirt (like when I'm going to the beach, etc). The S Pen slot is just an added benefit that makes the enormous size and ugly hinge protector a little less unacceptable.
Just my 2 (or 3) cents after having tried and tested a ton of different cases for this device, for what it's worth...