I can see why you would think that, but I'm afraid I disagree. I tried notifying players of their pillars and asking them to remove them. I stressed it needed to be done right away. However, the problem is that much of the gameplay on the server centers around travel. It may be hours before the player returns to that pillar, even if they went straight for it (and they won't).
Then the admin will forget about the warning, the player will forget about removing it, and it will still be there. We had 3 pillars along a single trade route after just two days, and with only 8 players. Imagine how many there would be after months of play with 50 players.
No, I'm afraid the punishment must be immediate and harsh. The details can be negotiated with the player involved. A warning should be given, but the player should not be given much time. Enough to grab a shovel, but not enough to get to a safe port. It's up to the admin.
Bottom line: if you don't want the punishment, don't commit the offense.
Now, on to "annoying". I will remove that language, but I can't help the feeling that I think you are nit-picking here. If you are constantly following someone everywhere they are trying to go inside protected airspace, you are probably trying to harass them. Why else would you be doing it? Obviously being in the same town as someone is not harrassing them. Having 4 guys stay within 5 feet of a player with their swords out, that is. I ask again, why are you doing it? Are you trying to prove how mighty you are and intimidate them? That's not going to fly. Are you just trying to go about your business and unload your cargo? That's fine.
I think if you are honest, you know what I mean about "going after someone". If you are mad at Bob, Protected Airspace is not the place to do anything about it. The wilds is where you do something about it.
EDIT: Harassment will be treated much the same way it is in the real world. The alleged victim will need to convince an Admin they are being harassed, and the alleged perpetrator will be given a chance to defend himself. A valid defense against the accusation would be evidence that the activity was innocent. For example, "I was just going to the ore merchant, my ship is right over there and it's full of ore. I can't help it if Bob was going to the same merchant." Also, the Admin will take past events into account when determining if harassment has occurred. For example, if Bob has recently attacked the alleged perpetrator, this will increase the odds that harassment will be determined to have occurred.