For Trading with Alien Grey you exchange intel for Alien sacks and assembling a toy you trade robo parts for robo sacks. I feel it makes sense to allow players to be able to repeat these quests because of the nature of them and because the items obtained as a reward are not tradable and there is no other way of getting them after the quest is over unless we make a new character and level them to 45. Could even be set to be repeatable after a duration of time if that is important for what ever reasons. I left out Rolly Polly 6 tools and Mac the Mechanic's Maintenance Manual because of the nature of the quest, how many times is Mac going to have his manual stolen by toys or Rolly Polly 6s tools though I wouldn't be apposed to these being repeatable as well and for those 2 in particular I would say a time reset is appropriate if you want to keep it feeling more realistic.
We kill walking mushrooms and flying witches on brooms. Giant dragon skeletons and bipedal cats that know magic. Books that walk and Bigfoot is apparently real in the Maple World. There is nothing realistic about Maplestory. Request whatever you want!
Yeh that's a fair point, I feel like things are more likely to be implemented if they make sense. but I guess at the end of the day its ultimately up to the once who have to do the work.