see here my second kingmaker map. It's pretty balanced (everyone has enough space, wood stone and iron are available in every castle estate) but as you can see the pieces of land are far from similar.
the map itself has 2 rivers, a lake (grants great tactical options like pictish boat warriors), the sea (lower left corner) a forest area, mountain area and the middle is a giant field with marshes for pitch. there are also two islands (one in the river, one in the sea)
the map has quite a few estates, two of which have a little fort (ar at least a wall) you can use as another layer of defence, or a place to safely produce certain goods.
personally I think it's a great map because it offers so many tactical options, as well as very different places, giving it high replay value. It's not the most beautiful maps I have ever made (I just used one texture for example) but it sure was a fun map for me. Please give your opinion!