I've been playing UO since before Trammel existed. I've run into a lot of PK's and PvPers. Yes, there is a difference. My only gripe with the system as it stands now is ganking. I've gone and tried to do champ spawns and have been ganked every time, usually right as the champ spawns, I lose my life and any chance of getting a powerscroll from it. I realize that as soon as I step into Felucca that I have signaled my consent to PvP, but not to get powned 4 to 1. I run with a small guild of friends, usually about 3-4 of us try to do the spawn and we'll get ganked by 6-8 reds. We're in the spawn, the majority of creatures have already flagged on us when we get jumped. I've given a few a run for their money, but in the end I just end up going OooOOoOoOOoo... I could care less about the insurance money or the bandaids and potions I lose or the fame. But the fact that those that end up with the powerscrolls have done next to nothing in the spawn itself to warrant getting the reward, irks me. It reminds of the days where you could jump a kill last minute, get one hit in and be able to snag a majority of the creatures loot. A fighting chance is all that I ask for, for an item that is Felucca only.
Perchance with the champ there could be some changes. Whatever party initiated the spawn would be flagged. If they are all eliminated before the spawn is completely finished (meaning the champ must be dead too) then it reverts back to stage one. This would allow the reds the chance at jumping the players at the end of the spawn to PvP for the scrolls, but it would also allow the PvMers a chance to escape with the fruits of their labor, not get picked off after they've done all the work and have some one else reap the rewards.
Perhaps making it so no more then two players could target another player at a time. That way you're free to attack whomever you choose, but giving the other a chance at survival. Ganking would be eliminated. And add a timeout on the targeting. Say you were attacked by A & B, with C standing by. B tabs out and runs, so C would not be able to flag for say 5 minutes. But if you were to attack C, it would clear the target count. The same would be applied to pets.
Also maybe make it so players were a little more like the savages when it came to tamer pks. Most if not all players have killed the monsters that you are able to tame, hence you would know how deal with them better. You be able to inflict more damage and possibly (who knows) maybe take less damage.
Those are just my thoughts.
And as one final afterthought....Yes all the powerscrolls are in Trammel, either from the few blues that manage to run the champs or from the red's alternate blue characters who sell them there. No one would go to Felucca to buy a scroll because a)You buy it from a vendor, get ganked, you lose both scroll and money or b)You buy it from a vendor, get robbed, you lose both scroll and money.