It would be a feature that allows the player to reduce their level to play contents from lower level without penalty.
DDO has great low and mid level content that is not enjoyed by players because of the fast rise in level.
Players could play with your friends in lower levels, and have motivation to keep items that become useless in the endgame.
The XP earned by a player with lowered level is used to advance the original level of the character.
Some changes should also be made in Repetitions Count. Should be implemented some sort of regeneration or ransack.
This feature would be Free for VIPs and available for sale in the DDO Store.