Geoffrey, welcome to the site.
You had asked for comments, and after considering for the night I am still of the same mind:
Please seriously reconsider refining the pathways, their position and use* when you are building the garden.
(*texture: those are pretty big hailstones
) ( this is closer to 'tobi-ishi pathway: http://windsmithdesign.smugmug.com/Portfolio/Windsmith-Design/15046829_4eypn#1123991421_kU5MY
) (Windsmith Design : Mark Bourne)
Quite critical is that the 90 degree angle of your 'hailstones' pathway island nexus is out of place. As is the 'direct in front' path to the machiai, as well as the planting. The machiai would be best partially obscured,.. etcetera.
The line of the main 'nobedan' pathway + corner as viewed from the machiai causes the greatest alarm, as it runs in line with the main view: this is like an arrow in the eye and will make it very difficult to relax in the machiai (unless that is the purpose+ we would need elevation atmosphere drawings).
And this also shows up as a 90 degree entry to your 'private' sitting area. These 90 degree entries are avoided as they are too abrupt.
The best solution is to move the pathway 'to the right', or far to the left through the bamboo forest, being ideal, however the mass and number of the stone setting should change.
May I ask that you post the elevation drawings that indicate the 'atmosphere' of the garden?
thanks.. enjoy the project, and thank you for sharing... edzard