Thanks a lot. That's useful feedback. Yes, the lines are very different in this map to the previous ones. The reason is that the previous maps had a parchment base. This allowed me to soften the lines by making them 50% overlay and 50% normal. This resulted in a great dark brown ink effect. Now this map was onto a much colder blue/grey background so I couldn't get a nice ink effect so easily. I ended up leaving the lines at 100% normal - and you are right, they are a lot stronger than the previous maps. I'll have a shot at this and see if I can soften them.

I think you are right about the colour difference. I'll play with warming up the base layer a little and see what it looks like. And C&C is always appreciated. I'll be using this map again and again so anything that can be done to make it better is worth it. It is also useful to know what worked and what didn't as I'm definitely still experimenting.