I don't think it can be changed to drastically due to it being such an integral part of the game, i mean its called tribal wars. People play now mostly because its a game they know and have grown to love the format.
That being said, when you tweak the settings there could be more "fun" setting ideas like;
You can only join one tribe per world. There is no leave button.
You can only message people in your tribe. No outside communications,
You can only see the usernames of players in your tribe.. No outside communications,
They're not amazing ideas i'm sure people could come up with better, but i suppose the answer to your question is no, it can't be upgraded drastically without fundamentally changing what 'tribal wars' is, but i feel it can be tweaked.
Do you prefer the coin system or the packet system and why?