its a good idea but with the size of the middle part of ruemon it wont accomodate all of the players and definitely will cause too much lag.
My suggestion, create an NPC that will teleport to Ruemon all those that will participate RvR, thus not enabling anyone to enter Ruemon without going through this NPC. Upon teleport, a player should spawn to the area in a random place and not spawn in one place to avoid ganking by enemy players upon spawning or to avoid waiting on 1 specific place. Every time a player dies he will be teleported back to town where everytown should have this NPC that teleports back a player back to ruemon. IMO, this will entice anyone to join RvR and it will also avoid or possibly remove camping.