Furthermore, if I were you, I would put alts in other guilds and try to become apart of their PvP teams, and I would encourage my friends to do the same. This way you are actually showing you're sincere in your want for competition, and have no problem helping them get there.
As for 3-capping... Going back to the baseball reference. You don't swipe bags when you're up by 5.
"Not only am I going to beat you to the ground, but I'm going to shove your face in a steaming pile of ****, too."
Not really classy, OP. It's not classy for them to leave the RWZ either, but I wouldn't show class to someone who shows no class to me.
I agree, which is why I'm raising an Operative on the Imp side, while building their gear on my main Pub side. Imp side on my server is drastically smaller, has less good players, and sadly has one guild that -could- field a ranked team, and rarely does.
As for your last point, I can definitely see that. As an individual, I wouldn't 3 cap if I knew we would win (past/near the point where they need a 3 cap to win). However, I also realize the other team (and even my team mates) will have no qualms about doing so. I don't see beating an enemy soundly as malicious, which is why I rarely get mad at the other team for playing hard/well.