I actually only play on one character, but I'm kinda a completionist, so I enjoy getting that "100%" in fx world completion.

I have alts though, for sPvP.

On my primary account I actually completed the core story on all 9 characters/professions. But from there on (Expansions + Living World) I did the story and mastery unlocks almost entirely on my 2 Mains. Sometimes following up with another character, if I was missing an important achievement, e. g. for a legendary trinket.

Well, I did the EoD story until reaching Kaineng (incl. Seitung map completion) for the Jade Bot stuff (and some missing hero points to fully unlock all elite specializations) on all 9 characters/professions on both accounts.

Map completion is a different story. I'm aiming for 100% (at leaast all hero points and all waypoints) on all maps and all characters (on 2 accounts). Which means that I'm not running out of stuff to do any time soon.

I liked completing maps in order to prepare my way to get legendary weapons with the gift of exploration. After I got all 1st generation leggies, I stopped and now I almost puke only thinking about doing it another time. And for personal story, I only completed it once with a Sylvary and I loved it. Other characters, only done until our beloved friend dies.

I do maps completion on all chars, not done all 20 yet but working on it :D

As for story I only do it on one char, 2-3 max if required for achievements.