I just want to point out that we already have topics covering this, you can find them here:
https://www.pantheonmmo.com/content/forums/topic/2943/my-only-raid-concern
https://www.pantheonmmo.com/content/forums/topic/1348/instanced-versus-non-instanced-areas
Both large discussions covering raiding and open adventuring instanced vs open and it goes into great detail on lockout timers, preventing guilds camping etc. and it took all but 5 seconds to find using the search function ;)
For that reason, I will go ahead and close this thread, please feel free to join in on the other already active thread but keep in mind a lot of these posts have already been mentioned/posted so be sure to read through the thread before just copy/pasting your ideas.