If there were ever to be an area that is open for all to PK, I think the death realm is an ideal candidate for the following reasons:

- PK in death realm causes less 'grieve'. Since you're in Death realm whatever you were doing has already been disrupted, you were already going to face dakkru's curse. The only additional grief of a PK is that it 'll take you a little longer to exit the death realm.

- The atmosphere lends itself to it perfectly, in fact the PK would add to the atmosfere of a world you'd want to avoid

- It's a place most people have to go trough sooner or later, even if they don't like PvP. Whereas if you implement pvp in an isolated map, it'll probably end up being a desolate place (making the implementation more or less useless).