The split of Fate and Tsuki pretty much is Nasu saying hey I want Tsuki to have its own cool world breaking fights with vampires and uooohhh seggss sisters and nuns from the Church. No Servants taking the majority of spotlight in Tsuki and no vampire society taking the majority of spotlight in Fate.
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As the cast of servants already near 400, it is much harder to pinpoint an "average" servant. You have a lot more irregular cases and extra classes. It is much harder to fully gauge a servant in a such a broad setting like FGO too, and only in a few cases that you see one having a story/event chapter dedicated to showing what they are capable of, or your best bet is a VN or LN with a small cast.