If we do not get a lot more snow, this summer there may be water source problems doing the north rim from Big Oak Flat. I still think it is too low. The sun really beats on the north rim. I am a real shrinking violet! 7,000 feet is even to low and hot for me in mid-summer. That is why I did not suggest the Pohono Trail (south rim)- which has more viewpoints than the North Rim. Both are more spring hikes than summer hikes. My vote is to take the bus up to Tuolumne, start here,stay high, and then just come back to the Valley the last few days. This leaves the heat to downhill sections only. You could luck out though. I remember one summer we were climbing up at Tuolumne and it was unually cool so we quickly drove down to the Valley and did Royal Arches. Because nobody does this very popular route in the summer we had it all to ourselves! I also nearly died of dehydration and heat exhaustion on doing a route on North Dome in June, the day the weather turned hot. The "spring" on the top was bone dry. We were on the rock wall all day in 90 degrees being roasted by the sun.

Another suggestion- if you are going solo, I have never found it that difficult to get a walk-in permit. So even if you get a reservation, you can probably change routes when you get there based on the weather. You may want to have a "PlanB" for overly hot weather or if your planned on water sources are dry.