due to most players' abuse of certain adventures, and full ignore mode on many, most other adventures...setup limits....say a player has to do 10 of each of certain adventures (pending on the player's level), before he/she can refresh the limit and be able to do them again by 10's...or 20's...
this way game will be more diverse and challenging ...
instead of many "wise" players just hammering 100s of some adv's, turning them from adventures into resources/xp factories