I think a good addition would be to implement and display achievements.
Different grades for the different difficulty levels of an achievement.

(as examples, these are the official ones from Tibia - I just changed the colour).
And the ability to see which character has done which quests. Like this:

The achivement would give some kind of additional feeling, comparability and hunt for difficult achivements, maybe even hidden ones.
(Cross 10000 bridges, loot 100,000 corpses, etc.)
Which character has done which quest is just a QoL feature.
Both suggestions probably with an option to hide/show it in the account management if possible.
Or not to show it in public at all.