Manely to the developers of the game.
Me and my friends all love spending time on the game and enjoy it very much. We only play for fun so none of us buys the yearly/monthly subscription and without that the game is a bit slow one you reach around level 50/60, you start seeing the daily limit pop up very often and can’t progress without spending money.
Some of us play only during events, and onestly they’re great, they provide a way to progress faster and enjoy the game more.
What I’m suggesting to fix this kind of problem is to either make more events (the wait in between events is just painfull), this is obviously harder for the developers, since there’s even more content to make, and a solution for that could be adding smaller events, with less levels and less rewards, just to give to the players something else to do (after finishing challenges and daily missions the gameplay gets slower).