It seems like the number of PvP interested people here is slowly rising (
yay ) if this trend continues the devs might take a deeper look at PvP at some later stage of development, which I would really approve (my first thread in this forum was about raiding after all 
)
One thing that´s pretty much for sure though is that PvP will be restricted to dedicated PvP worlds. So the devs would need to implement a way to encourage players to build/store their stuff on a PvP world (risk/reward etc.) without making it unfair to players that exclusively play on PvE worlds.
For raiding I´d like to see something similar to Clash of Clans:
On PvP worlds other players can destroy your build (maybe only by using explosive arrows etc.). If they manage to get access to one of your chests they are able to loot x% of the stored materials (no items, wearables etc.) and if they manage to destroy some core structure (beacon block) they get some extra reward (ranking). After that your beacon gets protected until you´ve logged in again (to prevent one group/player from locating all your chests and looting them again and again in a short period of time). As soon as you enter your beacon again it quickly regenerates all structures (within seconds or minutes) just like in clash of clans.
Regarding to bounty:
The only MMO with a real bounty system I know is EvE Online where it is rarely used for its purpose and mostly it gets just abused (friends killing each other and sharing the bounty between them etc.). So experience tells that bounty systems in MMOs rarely work, as awesome as they might sound.