Rewards for completed challenges
(Idea adapted from Arnerius's one at discord)
Some very marginal bonuses could be added as a reward for completing the Challenges, something like:
Game Over -> +1 stat points
5000EKs -> +1 damage in pvp
Hoarder -> +5% gold drop rate
Token of Gratitude -> +5% discount from the Event Officer
Merlin -> +3% chances for upgrading items with Merien and Xelima stones
Truly Majestic -> -1 damage taken in pvm
Old Soul -> +1% drop rate
Ultimate Tenacity -> +2% drop rate
That would add another feature and possibility to add some - even symbolic - bonuses in different situations, just like guild's Huntmaster or Raidmaster ranks.
Yes very good idea to give the achievements something worth achieving! About time you provided a good idea!