Part of it was to make each dreadnought stand apart from the other. The answer to that, I found, was freehand.
I tried to make the flame effects and the freehand very different on each dreadnought- especially the banner. Only one of the dreadnoughts has hazard stripe freehand on him at all, and the other one has bright flame freehand and scroll work instead.
Overall, I think the pair of them turned out quite well.