Looks like a very solid spec, nit picky stuff:

Screws for cabinet construction are fine

5/8 drawer sides, and ask for hard rock "white" maple

I am a blum guy, always have been...have always felt the quality was better, but truthfully have not held a grass slide in 10 years or so and can not say if they have improved

I always go with the HD slides on all drawers over 24" in width

Hinges, again I can only vouch for Blum

I can vouch for Grass hinges and glides, glides as good as possibly better than Blum nowadays. I believe Blum just updated adding adjustments to catch up.
Specs are good, screws likely means pocket hole frames which are common with local shops and semi custom manufactured. Select is a nice touch.

My quibbles would be source of the ply and formaldehyde content. How are the boxes "finished"? (I prefer melamine interiors, and ply can be sourced that way.) Can you spec thicker drawer bottoms for large pot and pan drawers along with the heavier glide upgrades?

Shelving is solid wood???? Are you sure it's not ply with a solid wood nosing?

For the doors, MDF center panels will hold up MUCH better than solid wood center panels. They are more stable and move less with the seasonal changing humidity. If you go with solid wood, be prepared to see a lot more "beauty marks" at the joins where the wood has expanded and contracted. The only way to stop that movement in solid wood is to maintain museum quality humidity control in your home.

Thank you for this extremely helpful feedback....museum quality humidity control...Hmmm. In 1880s house I would say our humidity and the outdoors are in pretty perfect sync!

WIll follow up on shelving and formaldehyde.