Well Tom & I lucked into a GREAT paddle on the southern end of Lake Powell. It is mostly away from power boats, with fantastic scenery and was a true "WOW" for us.
There is a tour company that takes passengers down the Colorado River from the Glen Canyon Dam to Lee's Ferry called "Colorado River Discovery" (www.raftthecanyon.com). For a fee they will load your boats on their huge rafts, take you upstream, drop you off below the dam and you can paddle back to Lee's Ferry. Its roughly a 12 mile trip down stream with a 6 mph current if you stay mid stream. A few ripples, but no white water.
We did it in a one day trip which was fine. If we were to do it again, we would get the last shuttle back up and camp at one of the beautiful campsites on the river (composting toilets and fire rings at each well marked site)and take more time going downstream. The canyon walls range from about 700 to 1200 ft on each side. There were lots of birds, some pictogliphs,and a few small waterfalls along the way as well.
We would have loved to do more exploring along the way, but since we limited ourselves to the one day we had to move along.
Oh! Tip your ride up when you load up and they will share some great places to stop on your trip down river.
Would do it again if we get back that way!