Advice on a one day climb in Yosemite August

With only one day in Tuolumne, I'd do Cathedral over Tenaya. More pitches of interesting climbing rather than slabs forever.

The Regular Route on Fairview Dome is great. Done and done.

And Yosemite Mountaineering School is the only guide service that (legally) guides in the YNP (I think).

Serenity/Sons?

Nope. Unless you want to fry in the sun.

Except for Quicksilver, every route reco'd here is a trade route that is highlighted in Select guides and in the SuperTopo guide. It makes sense that on your first visit you'll want to do these mega classics that folks are recommending. But it'll probably mean crowds. It's hard to get off the beaten track on your first visit.

It would be hard to argue with a trip up North Peak over to North Ridge on Conness... that's a full day sublime climbing , relatively uncrowded , and beauty unsurpassed ...