I've always loved the Desolation Wilderness. The easy access and the spectacular scenery of mountain lakes and granite peaks makes this my favorite destination in the Tahoe basin.
And if you head out on a hike more than half a day from the road access points, you can usually find some solitude. And once you are a day away, it becomes more like real wilderness.
The hike up Horsetail Falls is an amazing day hike and can be the start of exploring the south eastern lakes for several days.