About 50% of my runes are to NPC area's all over, the other 50% are random mob spawns that have portal chambers linked up near them for transit farming. I wouldn't make any changes to Rune Books until after you make spawns and portals more fun. For instance if your farming on Yssam you can bind to a chaos stone, kill a Baradron, Selentine Gholem, Dark Dragons, portal over kill another Baeadron and Bind stone recall back to start over. We tended to keep an alt around to bank it was about 30k in Loot pluse rares an hour for 2 people so barely worth it if you get zero PvP and have extra Tasks to knock out in the background. More PvE Circuits like this need to be added before Rune Books get mashed up. You shouldn't make changes to Rune books until you understand all the locations people are keeping runes marked. Every location a player teleports to should come up on the heat map to add to the metrics.