I'm not exactly clear on your itinerary here, but I'll add what I can. What day is it that you're actually headed out with your packs on? You've got 7 days of food and plans, but you also mention the 23rd, the 24th, 25th, but you're exiting the 28th??? If you have a permit for LYV and HD for the 24th, what permit are you going to be using for the 23rd? Are you going out for one night, returning to the Valley then re-climbing it all again from Happy Isles on the 24th? I'm a lot confused!
First of all, the Mist Trail is not the route to the Panorama or Glacier Point. And Illilouette and Glacier Point are not "down", but decidedly up from LYV. The Panorama is accessed on the JMT side of the Merced River, just beyond Nevada Falls. Illilouette Creek is viable water, as is the Merced, but, there is no camping on the Panorama or near Glacier Point. In fact, you need to travel well uptrail from there to be legal. At this point, it's probably best if you familiarize yourself with this map to see where camping is allowed and some of the regulations that go with it; anywhere past the arrow points is open camping.
https://www.nps.gov/yose/planyourvisit/ ... lheads.pdfThere's also no camping allowed on Half Dome, and water on the way up is very limited unless you know where to look. To camp beyond LYV you need a pass-through permit. For the purposes of climbing HD, after LYV, you have to be 2 miles beyond it to again, be legal. That puts you above the use trail up to HD itself, and the best sites and water are at the junction of the JMT and Cloud's Rest trails along Sunrise Creek.
Seven days of food and gear can take you to a lot of places far beyond what you've mentioned, and you have two sides of the Merced drainage going right now, the JMT/HD and up Illilouettte Creek. Two separate hikes that don't really take you that far out, and that most of us would honestly consider day-hikes with some camping thrown in. Let's see if we can get you into the wilderness, loop you back around, and get you beyond what hundreds of thousands of other people see every year. Got a good map? Let's beat this around and get you set up right.
And, the best trails for mid-July, shady ones not withstanding, are the ones that most of the people aren't on too.