Definitely Cottonwood lakes.

For one, if you're really coming from the Malibu area, it's only a 4 hr drive to Lone Pine vs 5-6 hrs up to Bishop creek/June lake area. I don't mind driving, but that extra 1-2 hrs changes a lot of things, including fatigue, time leaving home, logistics, etc.

Two, the closest lake is 4.5 miles from the TH. Even better, it only has 1k gain, which over that distance barely registers.

Three, the CWs are still one of the prime GT fishing spots in the Sierra.

Four, it would give you an intro to a very popular back-end route to Whitney via New Army.

SF lake:

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I took my son up to Whitney via this route when he was 14. Guitar lake before summit/exit the next day:

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6 years later on our JMT section hike last year (Silver pass):

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