I just wanted to say a huge thank you to @Nut for this post. THANK YOU!
I've had the Vive since May and, while I've always loved it, I wasn't ever too impressed with the FOV and overall sharpness or resolution that was possible. Well, I had never bothered to actually measure my IPD or adjust the horizontal/vertical positioning like you describe.
But after seeing your post, I finally made those adjustments yesterday, plus I removed the foam and inverted it so it rests lower on my face and closer to my eyes... and the overall improvement in clarity and field of view is amazing!
So here's what I do with my Vive that doesn't get enough word of mouth around here. Virtual Desktop!
It's the closest thing to a killer app I've found for gaming. If you're only enjoying VR-enabled games and applications with your VR goggles then you are seriously missing out.
It's true that most AAA games don't work smoothly in Virtual Desktop. Frame rate stutter and screen flicker will ruin games like Dark Souls III or Watch Dogs 2. But depending on the capabilities of your CPU/video card, you can enjoy some astonishing results with less-demanding indie fare. Anything that can tolerate being rendered twice across two monitors.
By default, all Steam games will launch into a Game Theater in Virtual Desktop. This is a hopelessly lame screen setup with very limited, barebones settings. So the first thing you need to do with any game you want to try in Virtual Desktop is go to your Game Properties and uncheck the box marked "Use Desktop Game Theatre while Steam VR is active." Now when you launch your game in Virtual Desktop, it'll stay in Virtual Desktop.
The beauty of Virtual Desktop is that you can adjust the Screen Size and Distance sliders from an IMAX-sized screen smack up against your nose to a little TV screen floating way off in the distance... or anything in between.
So your screen can be flat and huge and maybe that floats your boat, but check that little box next to Curved and the magic really starts happening. Now you can wrap the giant screen around your field of vision. My favorite setting for loads of titles is to have the Distance slider almost as far out as possible while the Size setting makes the edges of the screen just out of sight at the top/bottom of the image and the left/right wraps around your natural field of vision.
Try American Truck Simulator where you have to swivel your head naturally to the left to look out your driver's side window and to your right to look out the passenger side window. And the open road fills your entire windshield. Stunning!
I recently played through Inside in its entirety (GAWD, such a great game!) in this giant-curved-screen format and it was amazing. And now that Nut helped me improve the overall resolution and sharpness of the entire image, I want to play through it again.
Hyper Light Drifter, The Flame in the Flood, Steamworld Heist, No Man's Sky, Owlboy, Abzu, The Witness (WOW!), Salt & Sanctuary, these games are given a whole new sense of scale and visual presentation and giant-screen immersiveness. It even works with a handful of AAA games like Doom.
Also worth trying, check the box that says Floating so the screen gets off the horizontal plane. Recline back in your gaming chair and rest your head and let the huge game float above you at a 45 degree angle. Lie down in a beanbag chair and play I Am Setsuna as if it's projected on the ceiling.
In conclusion, THANK YOU, NUT! And also, if you're only playing VR games with your VR goggles, then do yourself a favor and start indie-gaming in Virtual Desktop pronto!