This is my own personal theory only, based on my experiences with four Wishbasses.
Firstly, I play a number of basses with traditional thin neck profiles, and have no issues switching to my WB's. I find the thick neck to be very comfortable. It also makes the neck very stable, eliminating the need for a truss rod, keeping costs down, very Wish-like. Still, he offers truss rods as an option, and is usually very accommodating about customizing.
I also have found that I can achieve very good intonation on my WB's using his floating bridge, just move it around til you find the sweet spot. Adding a traditional bridge is usually possible on most of the body styles. Some though, don't have enough room at the bridge position. Plenty of folks add a metal adjustable bridge, but the floating corian bridge is quick and cheap, keeping costs down, very Wish-like. Wish also claims that not having any metal in the path of the strings contributes to the sound of his basses.
My theory about the high action, is that it helps to mask the dips and bumps on his fretboards that I have found, to varying degrees, on all my WB's. My WB's played buzz free when I got them, but when I started to experiment with lowering the action, I began to get buzzing on parts of the fretboard. Leveling and radiusing the fretboards has allowed me to set very low action. The minor adjustments I've done myself with just a straight edge to measure with, and a radius sanding block. The really bad ones I've taken to my local luthier.
I love my WB's, but I've had to put some extra elbow grease, and a little more cash into each one. Hope this helps you decide if it's right for you. Also, I have a very long post on the previous page you may find helpful. I talk about some bridge issues and solutions. Best of luck, James