Cloudripper via Green Lake is about 14 miles round trip. It's about 3.5 miles with 1600' elevation gain and 300' elevation loss to Green Lake. It's about 3.5 miles with 2800' gain and 400' loss to Cloudripper from Green Lake. The elevation gain and loss is about 4,700' over the entire 14 miles. It can be done as a long day trip or as an overnight trip with camping at Green Lake.
There is a trail to Green Lake and then from Green Lake to the wilderness boundary. You leave the trail near the wilderness boundary and hike on easy terrain until the base of Peak 13374 (Vagabond Peak), then you scramble over Vagabond Peak on a jumble of rocks that are easy Class 2. Once you are over Vagabond, you continue to the base of Cloudripper and scramble up the rocks to the summit of Cloudripper. I can't remember anything more than Class 2 terrain on the scramble over Vagabond or up to the summit of Cloudripper.
Mount Agassiz can also be done as an overnight trip or as a long day trip. It's a trail hike all the way until Bishop Pass and then it's a scramble to the summit from there. You just have to be careful on the loose and steep terrain.
I haven't been in the Sierra that far north recently; so I don't know first-hand about snow conditions. Based on reports it sounds like there's still tons in most of the Sierra. By August snow won't be as much of an issue.
I did both Agassiz and Cloudripper solo with limited experience; so I guess it can be done by someone who is solo and has limited experience scrambling around on Class 2 terrain.
The words "limited experience" are subjective though.
Just be careful and always try to know where your feet are going to go next if what you step on doesn't hold.
Here's the route (more or less) I took up Agassiz from Bishop Pass:
http://kathywing.smugmug.com/California-...413_K7yS8-L.jpg