Walked the Frances in 2007 and then 2012 through '15 to then walk the first part of the Norte and then the Primitivo. And at the time I did not opt for the Norte or Primitivo due to density but beauty and the fact that I had always wanted to wlak the Norte, but back in the days distances were too great between albergues.
Last May I walked the Primitivo and HATED how I felt after reaching Melide and the hordes of tourists. I had to gather myself and dig into meditation practice not to get the new reality interfere with the wonderful days I had just experienced on the Primitivo.
There is no denying the Frances offers an unusual mix of beautiful landscpae, history, architecture, but the people!!!
I just walked the Portuguese from Porto, and thanfully with the Espiritual variante. Had it not been for the variante I would be a very
pilgrim, but the again it's not about beauty but outting a foot in front of the other, although what brings you to tears is the beauty, and grace that comes with it. And the social as'ect, for non Germans, who make up a good 75% of those on that route these days, is dismal. But then again, you will be walking with hubby.
SO... you would not catch me on the CF between May and November due to the tourigrinos. I would recommend the Norte and Primitivo, although I want to see them untouched ... But if you like cafe con leche here and there Portuguese from Porto may be a good option.
Have not ealked the Norte, but the Santiago to Fiaterra and Muxia are gorgeous, if you are up for a shorter walk, or combining shorter walks.