Very nice. It's very detailed and very easily readable. I think even my silly cat can work it out .
Personally, (just started) I love the map exchanges. They usually demand around 5000 for the maps if I offer my maps too, but I can grind it down to 1500-3000 usually. I think it also relates to how much information they have.

One important thing that you might want to add to the guide is that if you get the map information, it's permanent. So if another faction takes over a region which you can see on the map, you see that! Even without units present! For free! (So basically you only need to buy map information for all regions just once.)
However, if the faction you bought the map info off expands into other territories, you don't get those for free (need to buy/trade for map info again).

Maybe I'm a bit unclear, so I'll use an example:
If you buy map info from the Gauls, but Germania takesover a region from the Gauls after you bought the map info, you can see the change in owner on the minimap.
However, if the Gauls expand after you bought the map info, you don't see that.