create a way for players to choose the level of their plants

If there was a way to choose the levels of our plants, that is, lower the level and then return to the current one, there would be no reason for players not to put all their plants at the highest possible levels.
so players can enjoy the new events which tend to be quite easy with lower level plants, and then go back to the higher levels to play Arena and Penny's pursuit.
This would be simply amazing and could revive a good part of the game, as well as bring new people into it.