Brain, Bytes, Back, Buns - The Programmer's Priorities
I'd like to add one more "B" to OP's title: Body.I have found after many years of programming that how I take care of my body before I ever sit down is much more important than the environment I sit down to.  I have sat in over 100 offices of every possible condition (some you wouldn't believe) and have figured out that there's a "time warp" involved here... If I've taken care of myself, then I can function quite well in the worst client dump. If I haven't taken care of myself, then the most expensive of everything won't help much.I have had scoliosis my whole life, so I've had to learn how to take care of myself or I never would have made it this far. Some of the things I always do:  - jogging (3-4x per week)
  - body weight exercises (I love Hindu squats and push-ups.)
  - stair climbing
  - proper eating (a whole subject itself)  
  - monthly chiropractic visits
  - getting out of my chair every hour (a must for ANY chair)

Oddly, I have never really followed most of OP's advice because I never thought it was very important. Most other programmers can't believe me, but here is my typical arrangement:  - cheapest chair from yard sale
  - cheapest (disposable) laptop (currently $350 Lenova)
  - one monitor (I can't stand > 1; I lose my focus.)
  - good keyboard & mouse (the only things I don't skimp on)
  - any work surface, as long as it's lower than 29"
  - at least one feline companion

OP brings up some good points, but the most important thing is to find out what will work for you for years. It's a marathon, not a sprint.