Here's an idea iv suggested before.
CC quests with high Xp reward, to kill isle 1 bosses, to kill bosses on mainland ( sea, lake, demoness, kratt, genie ect ) and to kill chainless bosses.
Chainless bosses should give higher award due to difficulty.
Mainland bosses should give low rewards ( less disturbs for farmers ).
This will give players more opportunity to obtain more CC and with high Xp reward, it will help draw in those who are trying to level chars lvl14+.