I won't be any help with advice for things around the Grand Canyon to do
We did the North to South Rim hike a couple years ago, and coming up the south is tough because the last few miles are just switchbacks going right up the cliff side and it's tough when you've already hiked ten miles that morning. This is also where the main tourist location is, so as we were getting close to the end we started seeing more and more people just strolling down into the canyon from the entrance with their cameras and flip flops and whatnot, while we're carrying water packs and dripping in sweat. A lady who looked like she just came from the country club with a light sweater on her shoulders looked at us and said, "Wow you look very tired.....is it more difficult going back up?"