new quest system,
-timed quest, killing 10 ogres in X min, etc
-guild quest, clearing maps or killing 100+ monster
-killing a quest boss whos in a custom map, like instances said before.
-find some npc whos lost in ml or another map (long time ago in private server there was an event where cities had to protect custom characters, there was Lady Xelima and Lord Merien, you had to rescue and escort them outside the map, that map could be a custom one or maze or infernias)
-finding some items and parts of monster, when i finish it you get a weapon or a something made of those items.
-WANTED quest, killing someone or a stronger monster
and better prices like exp, contri, stones or some items like invis, sex, summon pots, maybe slates etc
better prices harder quest, ppl would play to get some items for sure not grinding like crazy to get dk+15 or a drop.
I dont beleive its really hard to get improved quest system... at least its easier than changing the whole game tho