I have to admit that Geography doesn't ususally belong to my greatest strengths, but I try to come up with a few details, which I think are important.

Again, here is the - preliminary map of the setting, but it features only the coastal lines and the larger political entities. 

The main setting of the  Dark Golden Age is based on one big continent surounded by several islands and the like. The very North of the continent lows beyond a theoretical polar circle and is thus covered permanently in frost and ice. Below this, there are the typical boreal tundra and taiga belts, before the climate becomes more moderate, roughly along the line of Southern Rhyrgia and the Northern part of the Eastern League.

The very South of the continent  - the southern coast of Venna and Ferron and the Whale Islands are a subtropical, arid climate. This means that the North-South expansion is roughly about the distance between Iceland and Sicily, or Anchorage and LA.

Don't ask me about  winds and sea streams, but if I am not completely mistaken, the more central parts of the continent like Northern Thuria  is probably quite dry, with a certain chance for desertification (which probably works best for the Sarkan tribelands/Thur border region, including a quite cold desert, like the Gobi).

Several large rivers cut through the land, as there are several mountain ranges. There is very likely the typical terminal moraine low mountain ranges in the North, with the land beyond very flat.  On the other hand, there is likely a fold mountain range along the typical tectonic plate rifts, for example between the Ferronian Peninsula and the rest of the continent, and perhaps again between Sabscria and the rest, creating powerful rain shadows and comparatively fertila (or swampy) regions.