I think we will be using an open air frame setup, but I know I would take the 35 db fans at 63C over the 60 db fans at 56C every day.
On GTX 1060 the quieter fans are fine for cooling but I think on 1080's or Vega 56's the only option is to go with high power ones that are loud. I am still waiting for my shipment of 1080TI's to arrive to do some testing with them.
Yes, I think you're probably right there. The higher power GPUs will definitely take stronger airflow to keep cool.
I'm about to contact support and ask if it's possible to modify an existing order to add RAM and a M-SATA SSD.

I think the spacing is a bit too tight for 200W+ 1080Tis so I'm planning on using 120W 1070Tis with this board and continue using traditional risers for 1080Tis.