" Is there anywhere that you can start a little closer to elevation and hit a good loop, say up to 40 miles? Thanks all!"
A little further north you could go in over Paiute Pass, drop down to the JMT, follow it through Evolution Valley/Basin, and exit via Bishop Pass. That's a pretty sedate hike, less than 40 miles, and traverses some pretty nice country. The Paiute Pass TH begins at ~9400' and ascends gently over ~5 miles to Paiute Pass at ~11,450'. From there it's all downhill to the JMT and a gentle ascent back up to Bishop Pass at ~12,000' some 20 odd miles later.
It's technically not a loop since you start at North Lake and exit at South Lake, but you won't have much trouble getting a ride back up to your car. This loop is about half in Kings Canyon NP and half outside the park.
Edited by Tom.
A nice overnight side trip on this route would be to hike up Goddard Canyon and spend the night at Martha Lake, then drop back down and continue your hike. Pretty country up there and not a lot of people.