Breaking test room and new players? Please tell me the relationship between those 2.
Possible to change to location of the newbie center? Consider the location strategy, the room is located at "abandoned" area of fcity.
Some minigame inside, such as the marine sphere game? I can't really remember the name, last novice stand? Need 5 players to start the game (refer to speed race), encourage them to talk to other players, winner get 1 million zeny. Minimum reward to avoid players from cheating.
Treasure hunt? Create some quizes and let the new players to find the npc in fcity. Reward should be 1 million zeny. Could make the npcs like those in ring quest.
Scavenger? The items should be selected randomly. Like 100 empty bottle. Reward: 5 million zeny? Reward < market price.