It is chaotic, and that particular opinion will likely not change for me. People are on the move here, going every direction, on foot and in cars and trucks. Street vendors or beggars approach cars at stop lights and entertainers do acrobatics for spare change while you wait. Trucks and buses rumble and belch smoke, and motorcycles scoot between slower moving vehicles.
The city became less scary this trip and I felt more comfortable here because we spent so much time with our brother-in-law, Nelson, running errands and sightseeing. Nelson's willingness to jump in the car and take us wherever we wanted or needed to go made our stay with them so convenient and comfortable. We benefited from his knowledge of the city--the short cuts, the history, and about the way things are done here. It made the visit to the capital all the more interesting. And we felt safer as we learned how to make Guatemala City less scary.
Having tinted car windows that are so dark no one can tell what you have inside the car is one way to feel a bit more secure. Those motorcyclists I mentioned? Most are going from point A to point B, but some may be out to rob vehicles stopped at traffic lights. The tinted windows might make them think twice, though, not knowing exactly who or what is inside the car. Taking pictures? Don't spend too much time in one place on the street, pointing an expensive camera at every little thing. You'll give a bad guy time to figure out a way to take the camera away from you. Nelson would allow me a "hit and run" approach to my photography, letting me out for short bursts while he waited next to the curb or went around the block. Taking a cell phone on a car trip? Nelson always had his available so there was no reason to lose mine to a thief on a motorcycle. (On average, 61 cell phones are stolen in Guatemala--every day.) I made a habit to leave mine at his house.