Lyndon, we dayhiked to the Conness Lakes a few weeks ago, and those are some incredibly spectacular alpine lakes. The last one is a bit under 11.5K'. All use trails and slabs as your route, but nothing exposed or particularly steep for any duration.
The water taxi across Saddlebag can save you some time and mileage. From the landing on the other side of Saddlebag, it's about 4 miles to the last lake. Pretty decent dirt road between Tioga and Saddlebag.
