I didn't see anyone mention 60 Lakes Basin.
I've never been there personally, but I intend on going there this year either as a side trip on my planned JMT hike with a friend or through another Grand Rae Lakes Loop Hike. The trip in there is mostly trailed if not all trailed by now and the views are absolutely phenomenal especially at sunset.
The Upper Kern Basin is also a great choice that really shows off the majesty of the high peaks of the Sierra.
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