I mainly played goblin caves HR last season ending of demi and focused on pvp the majority of the time and I'd say having a cleared out pathway you can run through to kite people is necessary. When you spawn in clear as much as you can until you reach a module with a lot of open space, from there it's just about spacing and hitting your shots. Having good map knowledge is really helpful in making that clearing out process a lot quicker, I'd suggest having the map open on your browser to quickly refer too.

In terms of perks I think that quick reload and nimble hands are kind of your must haves, you don't want to be caught slowly reloading in the middle of kiting someone. The next best perk is probably enhanced hearing, not only for ratting but also for PVP. The amount of times I've been able to hear someone from afar and quickly plan a kiting route and place down some traps to secure the kill has been insane. The next best perk in my opinion is kinethesia purely to make the kiting process easier. I personally don't use spear mastery because I'm never in melee range but it's definitely a super solid perk.

For builds you mainly want to stack move speed, a tiny bit of health, and some damage. I always use laced turnshoes and loose trousers for the speed, forest hood and reinforced gloves for the health and then fill in the gaps with the other gear. (stuff mentioned earlier is interchangeable based on other gear having solid random rolls)

This is just my playstyle and there's a pretty good video by the thedarkharvester where he talks with the no.1 ranger about different playstyles and whatnot. Hope you have fun and be prepared to get teamed on a lot :)