I wouldn't bother with the Dura-Ace rotors. The ice tech rotors look cool, but are totally unnecessary for gravel unless you do very long, technical descents that warrant the cooling. The slotted TRP rotors are pretty good, and have built in wear indicators!
As for cable vs. hydraulic, I think it's absolutely shameless that Salsa sells a gravel bike for $2,800 /w cable brakes, but with compressionless housing the TRP Spyre and HY/RD both work well. A lot easier to setup and adjust / service in the field as well, but requires more periodic maintenance.