From the description of Crown of Stars:
Seven star-like motes of light appear and orbit your head until the spell ends.
My questions are: Are the motes invisible?
Supposing the motes are visible, do I still get the benefits of Greater Invisibility?
Again, supposing the motes are visible, "real-world" logic would tell me that if someone were to try to attack me, the difficulty of trying to hit an invisible person would be somewhat mitigated by the fact that I could just aim at the motes. Similar logic seems reasonable for someone targeting me with a spell.
However, (my reading of) the in-game mechanics would tell me that I am still under the invisible condition (as nothing has ended Greater Invisibility) and thus I should still get all the benefits.