Well there is only 1 game that has this type of PVP i wont get into names. Every day when the clock hits 8:30 in the evening the 2 factions fight to capture regions and on sundays fight to capture castles. You have to defeat its region boss to get the region.
I found this very unique and cool i would like to sugest something simular like :
On Sunday in like 8 or 9 o'clock the 2 factions lets say villians and heroes fight in 3different arenas in each arena there can be up to 40 people of each faction.
Well 1 of the factions must win 2 or more of the arenas if this happens the faction that wins gets award this can be a unique potion or a pet or something (each player gets it) (even if you are playing in the lost arena you still get the award if your faction wins the other 2 arenas)
Also sometimes it can be unfair because the one faction can have 30 people in 1 arena and the other faction 40.. so the solution to that is you can't have more than 5 players more that the other faction so its a bit more fair!
Put your thoughts in the comments !