I seriously can't believe anyone can look at those comparisons and chose a pocket other than E?
1. You're playing for A or D, you're not playing on tight pockets, I can tell you that right now.
2. You're playing for B, your speed control better be perfect, which is also true of A. Small errors in direction or speed will spell disaster in both these shots. With this length of travel, you don't need to be off by more than a fraction of a tip or just a little bit off on your speed. You can scratch, land on the rail, land straight in or come up short. Depending on your angle from the 6 you can end up on top of the 8 as well.
3. C and D are just a nightmares overall. You miss your position window by even a fraction, either way, the position can become from very difficult to downright impossible to pull off consistently. The side pocket can get in your way, you may have to shoot with speed with spins that many players are unfamiliar with. Stun run through, with sidespin, long distance....Yeah, I don't think any sub 600 fargos are pulling those shots off consistently. I'll be happy to be proven wrong.
I'm not saying I, or any other moderately competent recreational player can't pull these shots off. I'm saying that with a 100 tries, the successrate (given time between attempts to avoid "dialing in") is not even going to be close to that of E. With dialing in, it will still be pretty clear, I think. I'm also saying that some of you might be surprised at how difficult these shots can actually be on a normally tight (not gaffy) table.
"Insurance position" is a useful concept. Sometimes, like in real life insurance situations, the insurance is not as good as you thought it was. The very thing you needed has been carefully and precisely removed by skilled statisticians in a way that exempt you from compensation unexpectedly. Bad luck and pool Gods do this work in pool.