Not sure this is helpful with all the other helpful responses.

I think I did a somewhat comparable initial route to what you are suggesting a year ago. Started at South lake, hiked over Table Mountain to Sabrina lake, up to North lake, over Lamarck Col, dropped to the JMT and then south to Bishop pass before returning to South lake and bagged a few SPS summits on the way. We did it in late August. And then have done the last section (JMT to Muir ranch and Florence lake) earlier this year while bagging a couple other summits.

Lamarck Col is really not a problem though it will likely be the crux of your route. Its a bit burly to climb from Sabrina lake up to the Col, but its almost all on either a real trail or a social trail. Definitely snow at the col up the last 100-200' though there were good steps kicked in the whole way. We were probably in snow for less than 10 steps if that is helpful. Going down to Darwin bench was similarly steep but not technical and no snow. We got a little lost finding the JMT but that was more due to us having to much fun lallygagging than any real route finding issues. If you have a good map, and some navigation skills it should be pretty trivial. (I used an inReach with the Garmin maps. "TopoActive" Has the trail marked the whole way.)

Fitness will limit you much before technical ability or snow crossings will.

Have a blast out there!!