We are currently walking the Norte, in Otur ATM. We have walked CF and also Portugues and would say this is by far harder but also most beautiful. The hard part especially was the Basque country but also my favourite.
Whilst we may only see a couple to half a dozen walkers total during the day - which was definitely not the case for the CF, we have had to prebook accommodation due to limited facilities and also to ensure we can walk the stages we plan to - plus you have the local tourism also staying at Private albergues.
The challenging parts for us has been reduced services (coffee stops!) compared to CF, but comparable to CP. Also a lot more road walking than CF however less than CP. Also at times markings can be lacking, however we have used maps.me with the track downloaded and this has been very helpful.
If I could recommend a Camino route to anyone to do, it would be the Norte for sure.