We can all agree that the system of “here is a bonus to xp, but it applies to x number of games applied immediately, and only if used within 18 hours”, is very frustrating.
What I would like to see and what would make a very useful impact for players is to allow you to choose if it is applied at the end of a game. Still have a limited number of games it can be used on, and even keep the 18 hour limit if you wish (devs). However, instead of applying to your next game, you can choose whether or not to use it. So if you have a bad game, it doesn’t immediately waste it. Meanwhile, if you have a good game, and wish to extend your rewards further, then you can choose to apply it and get the bonus.
Just a major quality of life improvement.