I'm not going to do black/yellow stripes. That's a very conventional caution symbology that doesn't exist anywhere else in the Trek universe that I know of, at least not on the exterior of starships.
I am leaning toward the first version with the orange outline. It's similar enough to fit with what has come before but different enough to be unique. I'm working on the rest of the thrusters modules now, but they are a real pain to model, unfortunately. I'm getting faster as I go, but each one is slightly different depending on hull contours. Should have more updates within a couple of days.