@littlemisslukey lol I don't think it's the app that matters.
I use picsart and phonto, nothing's change there.
But I suggest you use lighting textures if you don't do already.
And trust me, what makes my cover look decent is filters. Try using vsco and there are some pretty neat ones on picsart that I suggest using. hdr 2, seafoam, drama, and dodger. Those are my personal favorites.
Sorry if this doesn't help too much but meh, only being honest here.