REH´s descriptions are very bombastic and romantic with silk and gold and gleaming steel in not so realistic settings. Maybe you can caputure some of that magic when painting the figurines. To me it would be kind of boring if you just "used vikings" for the Aesir and "Black Prince" for the knights of Aquilonia. I mean why? Then one might as well make a historical game. 100YW for instance...and say, well that is Conan the strategy game. But its not...everybody can see it is a historical 100YW game.
I realize this is a hobby project of yours but I am just discussing with myself here a bit. Would historical gamers buy such a game?..No, I think not because they would probably not like the weird mix of babylonians vs Swizz Pikemen and so on. (I would like it though...) Would fantasy-nerds buy such a game? ..No, because they look too realistic historical and not fun with pointy eared elfs and ents running around.
Everybody thinks of eagles when they hear Aquilonia, just as they think of grecoroman mythology when river Styx, Acheron and such appears in the Conan stories. Likewise the other national names, Mitra, Pictland, Ophir even Cimmeria can be said to be reminiscent of ancient historical or mythical lands. But obviously Stygia, Shem and the other nations are fictional fantasyworlds. They might look like whatever,
Obviously he must have read something, something of grecoroman myth even if he just used the names and cared nothing about the rest. Technologywise 100YW is probably a very good place to pick Aquilonian figures from. But no cannon then...