Yes, several people, including four or five of Steve's write-ups in the fiction section.
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Strongly roleplay the different factions. Use faction-specific names for everything. Use different map layouts, and even different layout styles. Make the factions feel as different as possible. Different tech priorities, different weapon systems, different design philosophies.
Ancient Greeks versus Vikings versus Zulus works much better than modern U.S. wet navy vs modern British wet navy versus modern Chinese wet navy, all using the same size engines, sensors, missiles & ships designs.