You're right that would be nice f you could dstroy your cards, i just got 1:50 minutes and i wondered if there's a higher level trainer than level 3
level = int(log(max(time-4, 0.1))/log(3)), with time in seconds. So any level is possible, 1.50 minutes should have given you a level 4.
But maybe your level 4 got lost in the huge pile, because yes, a destroy card feature is absolutely needed.
Look at this guy and his fancy calculations 😂
yes that is possible :)