Thanks, Snodsy! This is great feedback.

To answer a few of your points...

maybe more branching off the main rivers.
I actually had more branching of rivers earlier on and ended up taking some out, because it felt like too much. However I hadn't done the mountains at that point, so I could probably look at adding in a few small tributaries again.

Maybe take the Black dots down to a lighter grey OR maybe instead of a larger dot do a small dot with an outer ring stroke. The larger dot could be a little smaller and still read different than the small dots. Maybe same size - grey and black?

Could the roads have more spacing between dots or again grey.
Yeah, I can certainly take a look at this. I only did the roads last night and hadn't tried any other colour/style but black dots. I can easily change it, or space the dots out more.

The regional divisional lines aren't apparent - Make those grey?
You don't think they're clear? I had tried to make them stand out with a double stroke effect (I have a grey stroke underneath, then a dotted/dashed black stroke on top.) My problem with making them grey is that many of the regional borders run alongside the rivers, which are also grey. I thought it might cause confusion to have two grey lines near each other, though I suppose if one were dotted that would differentiate. It's trying to find the right balance between grey rivers, grey roads and grey borders. (I'm sick of grey!)

Wish all the mountains had the same line weight, the large ones are thicker.
Yeah, that's something I'm going to take a look at and fix the worst offenders. I'm using tiled clones in Inkscape. You can scale them, but you can't adjust the shape (while they're connected to the original, anyway) and obviously as you make them bigger, the lines get thicker. When I've finished everything else, I'm going to unlink the ones that stand out the most and manually fix them.

Shouldn't PORT LODAIR be all small caps like other major cities? Are you going to label the seas?
Oops, that's a booboo on my part. Port Lodair should have a small dot like the other smaller settlements. Well spotted! I'll get that fixed. Hadn't thought about labelling the seas, but that's a good idea. I'll come up with something for that.

The hills seem a little random and evenly spaced to a degree, especially at the bottom.
Yup, guilty as charged! I got a bit click-happy and was pasting them all over the place. I actually took some out before I uploaded the latest WIP. You should have seen it before!!

I feel that the hills are probably OK on the Plains area, as I wanted to give the impression of rolling countryside (a sorta LOTR Rohan feel) with few settlements and a nomadic population who travelled with their animal herds. But the region to the south could probably have most of the hills removed, or consolidated somewhat.

I was just reading an article on Eduard Imhof on type treatment, he suggests type above the river lines, since there are less descenders than ascenders, they sit better. (although your R's have that strong descending leg it may not be best)
I had two issues with labelling the rivers. Firstly, some of the rivers are very bendy and it wasn't always easy to have the type flowing round the curves, so I tried to pick the best place based on where the 'loosest' curve was. The other issue is that some of the regional borders are right next to the river. So I didn't want to have a label, then a border below it, then the river underneath that. I thought that might be confusing and therefore a label directly under the river would be better.

Is there any best practice on where exactly on the river is the best place to label it? What I mean is, is it customary to place the label near the mouth of the river, or halfway along or what? Or doesn't it matter so long as it's on the main trunk of the water?

Overall I think your type treatment has really nice divisions
Thank you. I used the IM Fell type family, which I adore because it has a beautiful italic, and also because it has a small caps font. I love spaced out small caps. So classy!

Just some thought,
I really appreciate you taking the time to share your opinions, and you've given me a few things to work on. Thank you!