What I would like to see is, even when the fundamental science is the same, that different species have different technologies and different focus on materials to produce their unique constructions. That different species value different things as luxury than others (whats seem abundant on one species home planet is scarce on others or what one sees as high quality others see as utter junk and primitive).
Just take a look at the early Stellaris, where empires had different means of transportation: hyperlanes/wormhole/warp drive which gave them an interesting twist and opposing factions need to adjust their tactics accordingly.
This difference, but pushed to eleven, would be cool.