Lore Question: What factions use what minis?

[TheAmishStig]

Ok, so...I may or may not have a long-standing diagnosis of Acute Figmentia, and between Dan's example painted figures and some chatting with Hunter, I'm second-guessing my original plan.

The original plan, when it was Set 1 and just Set 1 and no certainty over whether there would even be a Set 2, was to do each of the 9 armies I was getting...2 regular, 2 reverse, 2 green, 3 glowy...in a singular paint scheme, Ogres and Conventional Units both, on the assumption we wouldn't be getting Paneuro cybertanks; That way any of the paint schemes could attack or defend.

Now that Set 2 is here and doing fairly well, that throws a wrench in the works; I'm debating whether I want to split the attackers/defenders into different armies, counting on later sets to provide conventional Combine troops and Paneuro cybertanks to fill out the same.

So I turn to you guys, who know the fluff far better than I do: If I split them and paint up troops as various factions...other than the obvious two, who uses what empire's sculpts? I know of groups like Nihon and Vatican Guard, but not whether I should be doing Ogres or Fencers/Conventional Troops in their colors, or even [Vatican Guard aside] what those colors are.