to be honest, i tink open pvp will destroy the RP ambient.
the best idea to combine both i can tink of would be the restriction of area for pvp like have several spaces to do diferent things, but at the same time give those spaces a "racing" feeling for the players, sort of a objective thing.
examples: arenas (for 1 on 1, group vs group) raid areas (region control, guild vs guild)
on a side note: should a fighting guild(or a non job specific guild) should be called a guild or a tribe or something else?
In Asheron's Call apparently OpenPVP FFA no rules servers had elite leaders who became monarchs. the towns were relatively safe, and people organized/policed themselves. Sounds like RP to me.
*edit*
As Narure pointed out, I too would use auto-accept PVP if you could:
a) Be warned of it.
b) Be given a countdown of 10 seconds before the duel starts.
I've added B because someone could just walk up to you, challenge and hit attack straight away.. and by the time you knew you'd been challenged they'd already be taking swipes at you.
So what? i've been on full loot OpenPvP servers and you get killed before you even knew someone was near. Grab an alternate set of gear and maybe a friend, hunt them down. If you are in a good guild, you won't get attacked - definitely increasing the social aspects.
If the notoriety system wasn't borked in UO, that would have been the best PvP. I'm looking forward to vanguard full loot openpvp (i want destroyable towns too), Age of Conan and Darkfall most of all. Warhammer Online could be cool but it looks like WoW of PvP.
*edit*
I should point out that I want PvP to have a point, a purpose other than getting HK for crappy blue gear *cough*. If you don't want full loot, make it a percentage of cash on hand, with a little from the bank too. I want sieges and castles, territory and trade routes. I want my gameplay to affect the world. Ideally, if I save the princess, I want her to be saved!! (Chronicles of Spellborn is doing this and instancing old boss fights through an oracle's memories)
[ Please avoid making one post right after the other in the same thread. Just "Modify" your first post to add more information. --Karyuu ]