I didn't quote your whole post, because I'm not sure how to respond to parts of it. But I promise I did read, and I am really trying to consider, all of it.
This part I can say something about, though...
Originally Posted by hyperskeptic
On the personal side, I have to wonder how much trust and openness there can be in a relationship in which there is a real power imbalance. It seems to me motives would always be suspect: Does the student really love the prof, or only the status and possible advantage the prof might bring? Does the prof really love the student, or is the prof just getting off on the abuse of power?
I definitely hear what you're saying, but it barely applies to my situation, as far as I can tell.
I'm not in A's class, and although it sounded interesting, it's an elective I can definitely skip it if it means a relationship with A and/or E. A's not a department head or an administrator. He's the advisor for multiple clubs I'm in but the student/advisor dynamic is a lot more flexible than the student/teacher one, it's a lot more of a partnership from the onset.
Honestly, I see is very little power imbalance or ulterior advantage to this particular relationship, if it happens. The biggest thing would probably be time-management- I already ask A for help with a lot of events and ideas I've tried to pull together, and I wouldn't want something as stupid as a college luncheon (well, the favor-asking that goes with that stuff) to screw up our relationship. But we can talk that through, and it really wouldn't be the end of the world if I had to take a step back from organizing campus stuff together. I can definitely find another teacher as a platonic friend so that A isn't my go-to faculty guy.