Awesome list, man! 
I’d also suggest that people keep a written record of the signs and omens that pop up in their life and the events that follow them, as this can help identify recurring symbols that are specific to them. Just like using a dream journal can shed light on the architectural pattern of one’s subconscious, an ‘omen journal’ can assist in exposing deeper patterns woven into the tapestry of waking life. I go into this in more detail as well as some other techniques for increasing awareness of synchronicity and omens in my post here.