I would focus on three crucial things that are probably equally important at the current state of the game:
1) Make the Feedback Form able to be filled right off from the Client. It would certainly provide more fresh Feedback to the game (this feature would finally be popular). Needless to say, but make sure that the feedback form will be discussed monthly and shared with the community on the official page on a featured article. This will help to make devs, CMs and players more connected. With this space being opened, everything can be better explained and looked after (vocation balance, Free Account features, new areas/new mobs, etc).
2) Address in a very meticulous and incisive method the whole inflationary question on Tibia. Right now, the gold coins in Tibia are extremely devalued and the prices of Tibia Coins are going to the exosphere on many servers. We need to take important measures to remove circulating money on Tibia with a broad discussion between everyone who participates on the game. This specifically problem should be highlighted and exposed to the community as a collective problem that will eventually be even worse.
3) General review on current lore aspects and a better upgrade for bosses. Currently, important bosses that are supposed to be really strong are getting very weak, not to mention some arguable lore paths that the current game chose to be done. Just like I saw on a Reddit post yesterday, the current strongest monster on the game is a book. Take in account also the fact that you cannot differentiate an orc cultist mob from a traditional orc unit (which is really annoying when I see the creature of the day and I need to hover over it in order to differentiate what is there). I would look into classical areas and would also analyze alternative manners of putting more interesting things around on forgotten areas (without taking the classical atmosphere of it, just making it clear).
I know it is a personal choice over here and that Cipsoft may have different priorities when evaluating what is bad on the game and how it should be fixed, but I think that focusing on the three measures above would make our game extremely improved!