How many henchmen do your villains have to employ? How many baddies do the heroes have to cut through? Do they cut through 100s at a time, going through epic encounter after epic encounter? Or is it closer to maybe a dozen, perhaps 20 before the bad guy is out of people?
Which way you go can do a lot for the tone of the game. More realistic means fewer people, and that lets you dial things up slowly over time. More fantastic means more people, but that means you can risk ending up on the absurd if you're not careful.
Obviously it depends on the game,but even grittier games like L5R can disagree on if a Lord has a force of thousands, hundreds, or dozens and that heavily impacts the feel of the game.
So which do you prefer?