I think we should remove the victory condition for wonders in competitve games. If a player is owner of a wonder he should have a strong and unique bonus to overwhelm his enemy. If you have the ressources, you can counter with your own wonder or take the sacred sites otherwise you are in big trouble. If a player or team goes brainless all in, the player or team could lose the game although the timer of the wonder is finished.
Using the Wonder as a victory condition has grown historically. I really think we should go new ways with the wonder, because winning a game only with the wonder is really boring and an overhauled game mechanic especially in team games.
Another option for wonders could be defining one single place on a difficult spot on the map where it is possible to build a wonder. You or the team have to scout to find the place for the wonder. You have to expand to defend the wonder outside the own base.