I've trained a trumpet vine along a similar fence, and had considered doing the same with wisteria. The primary downside is getting to your neighbor's side of the fence to trim and train :-)

I would plant the catmint "underneath" the fence so it looks good from both sides of the fence. I would plant enough to make an edge like the above picture. I suppose if you want to add the climbing rose you could do so but i'm not sure you need it. I have a split rail fence and i also am planning on planting catmint as seen above. I love my catmint i have in my yard. it's beautiful land drought tolerant. I suggest maybe adding it to your other flowerbed as well.

I suppose they come in different heights did not want to "overshadow" the fence yet big enough to be noticed

I have the identical configuration you are speaking about with a three-tiered split rail and wire mesh. We did green wire mesh so that it would be diminished visually. Ours has been in for twelve years and still working just great, containing our pugs not our kids.