You asked for comments, so here are mine:
1) Overall, you're to be applauded for attempting to describe the nage/uke relationship. That relationship, the responsibilities each party has, and how those responsibilities overlap is difficult to describe.
2) I respectfully, and strongly, disagree with your statement that "Kihon Waza is a matter of experiencing a given form, and little else. . . ." Kihon waza must be alive and appropriate to the attack uke gives. While each party knows what is coming when the instructor says to practice shomen uchi ikkyo, nage and uke must each approach the practice as though they do not know the outcome of the technique. Partially this is for safety, as uke may give the "wrong" attack or nage may do the "wrong" technique. By being ready for anything, uke and nage can respond in a safe manner to an unexpected event. More to the point, if nage messes up in some way, there's no reason for uke to continue the technique as given. At the very least, uke may stop until nage can adjust and continue the technique, whereupon uke continues the attack.
Kihon waza should have the same spontaneity as shown in kaeshi waza, henka waza, and jiyu waza. In fact, we may be using the terms differently. Kihon (fundamental techniques), kaeshi (reversals), and henka (flowing from one technique to another) waza, can all be taught in a step-by-step, static manner or in a flowing and dynamic manner. One can use any of the three (not to mention oyo waza) during jiyu waza (free technique against either a known or unknown attack with one attacker).
The bottom line is that uke is much more of a teacher than the instructor. The instructor will correct nage or help him adjust his technique, but uke actually helps nage feel when things are done correctly or not.
3) To that end, specific guidelines as to how uke should attack would be helpful. We have a couple of guidelines at our dojo. For instance: uke should work to keep his hips under his shoulders while moving; uke should constantly try to get into a position to launch a good second attack after nage has responded to the first attack; if nage fails to take uke's balance or lead uke well, uke should not move; conversely, if uke has any doubt about whether he should fall, then he should fall.
4) You handle the safety aspect very well. Generally, we say that nage is responsible for uke's safetly, but uke is responsible for uke's safetly.
Leaning how and when to fall correctly is very important.
5) I think you have too much emphasis on the sempai/kohei relationship. I've learned a lot from my juniors and taught some things to my seniors. I've seen our instructor learn from us at times. I think the sempai/kohei relationship is more important to duties off the mat with sempai having more responsibility and needing to set good examples. Too much emphasis on being a kohei or sempai while actually practicing can lead to big egos on the part of sempai (at least I've had a big head for that reason, from time to time).
6) You state that is it not uke's job to make nage's technique "work." You also state that uke, like nage, is restricted to a given set of actions while practicing kihon waza. Some may see these statements as contradictory. I don't, and I think I see what you're getting at, but what should uke or nage do when the other breaks from those given set of actions? This should be clarified.
7) Overall, these guidelines are way too wordy. Guidelines are supposed to be brief and easy to remember. I would trim them to half the volume of words if you want any hope of a beginner grasping them.
I hope these comments are helpful and that they are taken only as constructive criticism.