Greets,
-I would give the οpportunity to every new player for a free 24-hour-VIP membership.
-I would give a boost to the "Disenchanting" skill for better results. Even up to dias/rubys.
-Free access to EVERY zone of the game at own risk(!) or as a trial visit with temporary gear/skills etc. Even inis. Everyone must see and know how big is the game and the opportunities that are available to the player.
-I would create a worthy help-other-player bonus system depending on the lvl difference, encouraging older players to help more and train newer ones.
-I would create diamond and ruby growing plants! Or a small garden in the house? lol
-I would name my developer day "Wish and fulfill day" giving one wish to everyone for one specific item and fulfill it.
-I would allow more permanent bank / bagpack slots depending on the character's lvl.
-I would put some more mailboxes. And ATM's 
-And I'd definitely create that Ferrari mount...
Then I would sit and enjoy a glass of wine by the fireplace! 
Happy Holidays to all!