So when the week ends and the leaderboard resets, the only thing the top 3 global players get is a badge. It is a cool reward but it could be better. Because they spent countless hours on the app to get there. Right now the first place has to spend more then 10 hours every day to get to first.
A simple way to make it better is that the plays that are top 3 on the global leaderboard gets colored names at the end of the week. So for example if a person gets nr one On the global leaderboard then the next week ( when the leaderboard gets reset) their name is shining in gold. And the person on second place gets their name shining in silver. And the person in third gets their name shining in bronze. And this will last for a week. Until the next person wins and then their name is in color.
This is a great way to reward players and making them feel special for all the efforts they put in.
There can also be a leaderboard where it says what players have gotten top 5 the most. For example player A has gotten global rank 1 four times.