Dungeon Master of Middle-earth
I didn't see anything like the Eye of Sauron with Halbrand. In fact, from his introduction in episode two, the signals were more of the "look foul and feel fair" nature of an Aragorn-like figure, whereas Sauron in the mid-Second Age is supposed to look fair. I'm curious how you got around the Eye of Sauron crater. I mean, it doesn't make a lot of sense either way, but it seemed like such a direct message from the filmmakers.Can't help you there. I've had that experience with other shows, but didn't get it with this one. It was obvious from the start that they were deliberately presenting multiple possible Sauron candidates and making it ambiguous as to which - if any - he was. I just accepted that as part of the premise, and kept an open mind.
ETA: The only way I can rationalize the crater looking like the Eye of Sauron is that it's some kind of bizarre coincidence, which is pretty unsatisfying. Another option is that we as audience members aren't supposed to care or notice and that it was intended to operate subliminally, but the inclusion of the image in episode recaps would seem to go against that interpretation. It seems like the show is punishing those who actually engage with its content.