orthographic vs. birdseye
I'm not picking on the map in question, but just commenting in general.
hand drawn mountains. definitely the way to go
If by "hand-drawn mountains" you mean those orthographic or semi-sideview peaks, which occur in a bazillion maps I've seen (I bring to mind the original maps in Tolkien's Middle Earth works), it's interesting to note that such features are usually the single exception to an otherwise totally birdseye-view or satellite-view map.
I was reading an awesome book about cartographic history at a friend's house ... I don't remember the name, but I can email her ... and it mentioned the development these orthographic mountain styles specifically.
Other elements are sometimes orthographic. Walled towns are sometimes shown from a side view, with gates visible in the walls, and towers rising from behind the walls -- in birdseye a wall is a line and you can't see a gate. Forests are sometimes shown as lots of trees with vertical trunks visible below their canopies.
I wonder if a mapper ought to consider whether to use all-orthographic, all-birdseye, or a mix, for each project. And if it's a mix, how do you choose which element gets which style?