This is a relatively small suggestion on some additions to wilderness PvM as I feel it could be more rewarding for both pvmers and pkers.
Krystillia in OSRS, is a Slayer Master who only assigns things in the wilderness. For example, she could assign you skeletons but killing them outside of the wilderness would not grant you xp.
I was thinking if she were to be added, she should be used for bosses only because currently, when the Captain of the Guard assigns you a wilderness boss, the quantity isn't very great so I think adding her to assign wilderness bosses with a greater quantity would give more of an incentive to kill the things nobody really bothers with like Vet'ion.
Monsters assigned by her also have a chance to drop Mysterious Emblems, which we use here as bounty money.
These next few additions will all tie in to the aforementioned suggestion about killing things that are not really killed in an attempt to make players want to kill them.
2. OSRS Revenant weapons.
In OSRS, there are 3 weapons (and a trash amulet) in the respective three attack styles that deal immense damage to things in the wilderness and the best thing about them is that they stack with slayer helms. I was thinking to either have these added to Revenant's, or Vet'ion, Callisto, Venanatis and Scorpia as these are not really killed alot. These weapons do high amounts of damage and would probably be preferred over the weapons you'd use normally which would give the reason for use in itself. They require revenant ether to charge which revenants would obviously drop and would make wilderness slayer (if one of these weapons were to be obtained) very good xp.
3. Wilderness Keys
When killing monsters whilst on a task from Krystillia, you have a chance to be dropped Larran's key. In RS, the main loots are just rune and other alchables and supplies. I think if we applied it to Runique those rewards wouldn't really cut it. A seperate table for these keys with a few things unique to that chest and that chest only would give great incentive to do these wilderness tasks thought I haven't thought of anything to go in there as of yet.
Overall I think these three additions would tie in really well with eachother and add a lot more to the wilderness in terms of pvm and pking.
EDIT: If this post gets enough credit i'll make a drop table for the Chest.