People can do whatever they want with their time. When you accept a 3 day/move game, you should keep in mind that it is within the rules for your opponent to use as much (or little) of that time as he wants.
The "Rate your Opponent" idea would get abused to the point that it wouldn't accurately reflect anything. Some people take losing hard; do I want those players to rate me if I just clobbered them in a game? No, I don't. Do I want to worry about getting a poor sportsmanship rating because I didn't say something as inconsequential "gg", or "Hello"? No! I just want to play chess!
i'm not so sure the "rate your opponent" idea is fool proof either, BUT a lot of things about this site are far from fool proof--live chess for one. but don't worry, 2.0 is just around the corner!) hahaha
also, this idea that people can do whatever they want with their time is absurd to even say. what gave you the impression that anyone doesn't understand that a 3 days per move game means just that? i'm not talking about forcing people to move more often than the time per move allowed. what i'm talking about is the annoyance of playing an opponent who is dedicated to moving quickly until he begins to lose. my opponent is logged in sometimes hours on end with no move. i know this s his right. it's also his right to intentionally fart in a packed elevator but i would expect him to wait until he is in a more appropriate setting... that's all i'm talking about. being courteous and non-churlish, regardless of your chances to win the game. or if in fact my opponent has a legitimate reason for his sudden laggard play, then a bit of communication seems warranted... especially since i asked him why the change in pace. all i got was silence. classy. i think we as a community have a right and probably a responsibility to address issues like this.
The "Rate your Opponent" idea would get abused to the point that it wouldn't accurately reflect anything.
I'm not that cynical about people. I believe most people are fair and would not abuse such a rating idea. If there's a player out there with a high number of negative reports from a high number of different players, that would be useful information. Ebay for example has been using a feedback rating system for years and it did not "get abused to the point that it wouldn't accurately reflect anything." It has stood the test of time because it works and people like it. People can look at the rating (including the reasons given for it) and decide for themselves who they will or will not do business with, or in this case play chess with.