Well, for the creatures with gravity pull and immaterial, it's usually because gravity pull was placed first, and then they were immortalized. If the enemy creatures still had to attck the gravity pulled target and it wasn't targetable then it's be impossible to win by creature damage as the immaterial creature could never die. So that's understandable. But as for things like rain of fire, it doesn't just hit everything, it has to target each creature and do it 3 damage. So I'm guessing it can only hurt the creatures on the field that it can target. Burrowed creatures can't be hit with rain of fire either.
So not exactly a bug, i'd bring this up in the new features area instead of here. As for the desync problem, yeah, desyncing is still really bad.