That scale seems to work just about perfectly with a line from the Betrayal of Falador book series, it was something along the lines of a trip on horseback from Falador to Taverly taking 2 days on horseback.
I overlayed a map of France with the map of Asgarnia and tried to roughly measure the distance from Falador to Taverly. It's just about the same distance from Blois to Alençon, 84 miles. 30-40 miles per day is manageable for horses.
I know the books are only as canon as they need to be until the game goes in a different direction, but it's still nice to see them match.
That does throw my map out of the window, it'd put Gielinor around the size of our Moon rather than the Earth. I'm assuming it needs to be that large unless the planet's Anima is keeping things similar on a smaller scale.
Yeah it's tricky. The two main factors for me are that at a European scale, the existing world is actually massive - we're talking hundreds of small towns and villages in each kingdom. It really radically changes the scale of the world and how you think about it.
On the other hand under the Heptarchy scale, the Zarosian empire (and the god wars in general) really seem like a bit of a provincial matter which gets a lot of press.
In either case we can always do a bit of a "reveal" (retcon) that there are other continents and the god wars were also taking place there, but that would be inconsistent with all existing ingame material on the subject.