I don't see a problem with having the various games in the same section, hell I don't even see the need to title them accordingly. The reason for this is if you put "MilSim" or Skirmish in the title you risk losing potential players. And where do you put "Scenario" games where you are playing the same scenario all day with a break for lunch? I've seen these games with ammo limits, camo restrictions, objectives and the like.
I can't say I'm a MilSimmer or a Skirmisher as I like both. Frankly I just wanna have fun.