Hello,I quite a ways back (I think just after Silver Surfer and the first Galactus event) and I am giving this a try again. I was never very well educated on the game -- and it has changed quite a bit in the mean time. It seems to be more fun than I remember.Anyway, I am returning after being in the 3* -> 4* transition. Of course, they have added a ton of 3*s in the mean time. I don't have any complete 4* -- most are 1-3 covers. Should I sell all of my 4*s to make room for a 2* farm (I dropped most of the 2* because there was not much reason to keep them back then)? Is there a threshold of covers I should just keep the 4* -- or a list of 4* worth keeping?It looks like I need to make a 2-3* transition all over again with the time away.