Open world PvP, Ive heard Yoshida is a fan of ultima online and they had nice open world PvP, this is where they could remove the GC restriction theyre precious about from frontlines to help queues and could implement the GC thing here. Have a toggle, perhaps speak to an npc at WD Pier, where you can set yourself active to Open PvP with a cooldown before you can turn it off again (iirc it was 4 hours in UO?) You could set yourself to Open PvP and it would put ur GC icon next to your name above you (like the mentor one) that way if you see a person with opposing GC icon you know you can battle. Ranking for K/D/A, Achieves ect.
I loved in UO having to be aware and susceptible to being attacked at any given moment. And traveling around with friends fighting other crews, with having the option to turn it on and off.
Thoughts?