I think most posters here would say that your timing is the issue at this stage of your hiking career. I see no reason that going later in the season would be a problem, although, Crabtree Pass could be a problem.
I am in my 53rd year of hiking in the Sierras and I remember quite well my first trip. I was 15 (I am 67 now), never been hiking and went with 2 other guys out of high school. We went over Kearsarge Pass and spent 7 days fishing and hiking. I learned a lot about the backcountry and equipment.
One more thought,there's nothing wrong with doing a reconnaissance hike to Soldier Lake (or any other location) with a couple day hikes around the area and then back out Cottonwood Pass.
paul
