Most people hiking down to Phantom Ranch and back usually go up and down Bright Angel Trail. The scenery is very nice but you really don't get to see the Canyon until you're almost near the river. Just in case you only make the hike once, at least hike down the South Kaibab trail and back up Bright Angel. South Kaibab gives you magnificent views of the Canyon that you can't experience on the Rim, nor the Bright Angel Trail. I've hiked up and down and across the Canyon numerous times and I'm still in awe of the beauty every time I make the trek.