Pretty much the title i'm just wondering so i could go and do them for when i make some alts so they can level quicker by accepting the arks missions

I don't have a list, but basically its any ARKS Mission that is related to something shared across the account, so primarily anything that involves getting a Title, Story progress, and, surprisingly, the unlocking/clearing of Expeditions. Character progression stuff like Level or Difficulty unlocks are character-based, so they need to be redone on each character.

@AndrlCh Would i be able claim the "obtain the level 75 class boost title" arks mission on newly created characters or do they need to be higher level for it to show up ?

@AxelYuki I believe that one is locked behind some level progression Missions, but as soon as it is available, it automatically becomes redeemable.

@AndrlCh Hm interesting i'll have to mess around with it some.. thank you for the answers!