Mod Gambit, Pvp is not just limited to "hunt down/kill your target while doing X/Y/Z". That is a very narrow way of looking at it imo.
Objective based Pvp can add a tremendously exciting aspect to bounty hunter, if done correctly.
Tasks like: "A mysterious emblem has spawned somewhere (random/in certain hotspot) in the wilderness. Retrieve the emblem to complete your task"
OR
"Enter the wilderness at level one and exit through the wildy lever at mage bank to complete your task"
In order to complete such tasks you will need to be carrying a certain amount of risk on you at all times (High risk, high reward).
By the virtue of carrying that risk, you will not be safe from other bounty hunters, which include your very own target.
These kinds of tasks don't necessitate confrontational- Pvp, but allow for far more diverse gameplay styles, incorporating aspects of stealth, tank testing, baiting and anti-pking
These tasks could even act as a suitable entry point for players new to Pvp.
Tank testing/out-maneuvering and generally being sneaky enough to evade death from groups of players in single and multi-combat in addition to the target following (or teleporting to) you to in order to complete a certain objective can make for extremely thrilling gameplay.
The task system can run in parallel to the target system and it could include tasks that involve defeating your target in a certain way (such as the ones offered), or other objective-based tasks like the ones outlined here.
Depending on how skilled you are, you can even complete your task AND simultaneously kill the target (or other attackers) following you to obtain both rewards. They are not mutually exclusive.
Bounty hunter needs a way to "branch out" to spice up the gameplay and allow for different play-styles.
Coupled with attractive rewards, I believe objective based-Pvp is the solution that you're seeking. It's the reason why minigames such as castle wars, Fog, Soul wars, Sc have historically been as popular as they have.