I am sure there are tones, but the one which is interesting to me is that it was not a dynastic empire, a single family on top, it was like a meritocracy, one of its kind, where in latter time even non Romans could climb the highest ladder.
It definitely shaped modern Europe in an unimaginable way.
What's the most impressive to me, is how they managed to get over of the most catastrophic battle in human history against Hannibal, losing 50-70 thousand people on a single day at the Battle of Cannae, and managing to completely turn over the situation.