I voted for jumping off of a moving ride strictly based on the scale of their impact.
Line cutting is obnoxious, but I never really have dealt with it much at all, so it isn't that big of a deal to me. Plus, it has very little affect on anyone besides making the people behind them wait an extra 30 seconds.
I'm from the south, so anytime a woman or child is standing, I am used to a man giving up his seat. Unfortunately, in much of the country, chivalry is completely dead and I am aware of that. Most people weren't raised to show respect in that specific way and I don't fault them for it. Yes, they should give their seat to the disabled, but they don't. In that situation, though, they are only impacting that one disabled person.
When I was a CM, I got yelled at from time to time. People got mad that Mickey couldn't come out when it was pouring down rain, that Tower of Terror wouldn't run in the middle of a lightening storm, that it wasn't right that we moved the tea cups from being in front of the big blue hat to the Magic Kingdom

confused3), to the lines being too long during SWW. I never really let those sour my day and it was really just me that they were impacting.
Flash photography on a dark ride is annoying, but I figure that many people honestly don't even realize how it can blind other people. I honestly think that if they realized that they were hurting other people's eyes, they wouldn't do it. And, as far as the impact goes, it really only affects those on the ride with them in their specific boat/car/etc.
Abusing the refillable mug is an obnoxious entitlement thing, but I don't think it is really in the same category as some of the other things listed. And who does it really affect?
Pool hopping is in the same category as the refillable mug abuse situation, in my opinion.
Carrying Your
ECV Onto A Bus While 20 Of Your Family Members Climb On The Bus Behind You is an interesting one for me. Many people opt to get the ECV rather than a wheelchair because they do not want to be a burden to their family by having to be pushed around. While many people who rent these types of things might not look disabled, they would be unable to walk around the park all day. They do need the assistance of a wheelchair or ECV to get around for extended periods, but can carry one onto a bus. Doesn't bother me. Also, it really doesn't affect anyone.
Photo bombing falls into the same category as the flash photography situation, for me. It's dumb and silly, but most people think that they are just being funny. My mom was trying to take a picture of my sister and me at Mama Melrose and the man in the booth behind us would always strike a funny pose whenever she went to take the photo. It was silly and still gives us a laugh when we look at the photo. I'm not a photo bomber, but I do try to believe that the people who are doing it really mean no harm and aren't fully thinking about the consequences and the fact that some people are very insistent that they have a pure photo with only their family in it. In this situation, the only people affected are those wanting a photo.
As far as asking a CM where to meet Harry Potter, that's just ignorance and I try to be patient with ignorance. They just got confused between WDW and Universal. It happens and isn't worth raising my blood pressure over. No impact on anyone, really.
Jumping from a ride is a completely different situation. Everyone knows not to do this. Even if it wasn't posted multiple times while in line, as well as said prior to starting each ride, common sense would dictate you not do this. But, some jackwagon still does this which stops the entire ride. This impacts everyone currently on the ride, as well as everyone in line. This extends to the fast pass line and even to those with a later fast pass. Then, you have the extreme situations like the one earlier this summer on Soarin' where it shut down the ride all day, as well as the ride at
Disneyland. Much larger impact, so it is the worst thing a guest can do, in my very humble opinion.