Couple of ideas

[Apophis2310]

Mail System:

What about adding a mail system for players to mail other players items, cash, maybe monsters (on pvp) haha

You could use an inteface similar to the character stats page to fill out the message and toggle through the item to send or input the amount of cash.

Skills:

Add craftable items and implement skills to create these items.
Similar to functions already in the game, like mining in the mines near khaz for ore / gems, using hatchet or axe to collect lumber out in the forest.

Familiars for mages:
Have a quest for the mages to summon a familiar, this functionality is already in the game as far as summoning skull from wand, but have this familiar give the summoning player a int stat bonus maybe +regen mana and the ability to sling some spells at the monster the player is attacking. Of course there can be different flavors of pet / familiar.