Okay, this is my first attempt at a map on the computer, and although the map I will end up using for my writing will probably change massively from this, I want to really work on my own style and get that more or less sorted, form a technique that I can follow and then maybe branch out when I'm a little better.

I have only drawn a basic outline along with drawing in potential rivers - I'm not sure if it's a little overdone, (especially in the marshy-swamp area just before the delta). I know where I want the mountains (two chains surrounding the north-east river, and then joining into one chain to edge the start of the other rivers, as well as a chain on the coast near the north-most lake, those are the main places). I have decided that I would like to follow a artistic style, and am following a great tutorial (I will post the link later). However, I am struggling to find a suitable scale to make the mountains. I have tried using brushes, and they all seem to look a little blurry to me, I have also tried drawing them, although they really are way too big (I may enlarge the map just to draw them in).
As a side note, when making your own brushes, what is the best resolution/size to make them?

Antique.png

I am open to all suggestions regarding them map
Thanks for your time,
Cekoti