Hi Goldberry,
Some thoughts on your mapped routes from my experiences in the park.
Northern Loop:
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Your northern loop is 101 miles with almost 24,000 feet of elevation gain, according to the Caltopo profile! And in my experience, Caltopo tracings underestimate the true distance by 10 to 20 percent. I think you have to be superhikers (or masochists) to cram that into one week. You show your loop going clockwise. Dropping the Grand Canyon of the Tuolumne and Hetch Hetchy sections and heading out on the PCT would make for a much more reasonable hike in my opinion (still way too much for this old geezer :-). You could always camp first night below Glen Aulin and then day hike down to see the waterwheel falls before continuing on the PCT up Cold Canyon.
Starting and ending this northern loop at Virginia Lakes (just east of the park) would keep you in the alpine zone longer than starting at Tuolumne Meadows. There is dramatic metamorphic rock scenery between Virginia Lakes and Virginia Canyon. Also, wilderness permits to start at Virginia Lakes are probably easier to get than starting at Tuolumne Meadows.
Your map shows a possible alternate at the western end of your northern loop. Your main route (red line) up past Tilden Lake and over Tower Pass is more scenic (in my opinion) than the Jack Main Canyon and Dorothy Lake Pass alternate, so I would drop that alternate. The cross-country above Tilden Lake and over Tower Pass is easy and quite wild. Plan to take the trail on the south side of Tilden Lake to the outlet, cross the stream, and pick up a good use trail that takes you all the way up the west side of the lake and a mile or two beyond before it fades out. I had a beautiful campsite overlooking the whole Tilden Lake from a little knob at the middle of the south side. Heading down from Tower Lake, you should be able to cross the West Walker River at the upper end of Piute Meadow rather than going all the way down the trail to the lower end of the meadow. When you get to Kirkwood Pass at the head of Kirkwood Creek, there is a nice campsite at the little tarn directly on the pass just north of the trail with a sweeping view of the whole valley and peaks to the west.
From Kirkwood Pass, instead of dropping down the North Fork of Buckeye Creek and back up the South Fork on the trail, you can take an easy cross-country route that stays high in the alpine. Walk up the slope directly south of Kirkwood Pass to pop out in a high broad meadowy basin at the head of Thompson Canyon. Saunter down the meadows to where the forest starts below 10,000 feet, and then start traversing up the east side to a low pass at 10,100 feet. You drop down the east side of this pass directly into Kerrick Meadow. There is some annoying micro-route finding needed right at the pass area to get around little cliffs. But I took my kids (7 to 12) over this cross-country route and pass with no problem, so I'm sure you can do it.
There is an extremely scenic campsite on a low bluff above the north end of Crown Lake. The upper alpine basin of Matterhorn Canyon is also an amazing scenic spot to camp. If the pass south of Upper McCabe Lake doesn't go for you, you can always drop back to the PCT and out. Or use my idea of starting and ending at Virginia Lakes.
Southern Loop:
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Your main southern loop is easy for a week hike at about 55 miles and 11,000 feet elevation gain according to Caltopo, although adding the optional 30 miles up to Clouds Rest and back puts you back in superhiker territory in my opinion. Be aware that starting at the Nelson Lake trailhead does NOT permit you to ascend the cables on Half Dome - and the ranger checks this.
For scenery and solitude, Nelson Lake is a good starting trail. Nelson Lake itself is my favorite campsite in the Sierra (been there on 9 separate trips - and only shared the lake with others twice) - camp at the edge of the trees on the northwest end of the lake to watch the outstanding sunset color on the cliffs to the east. The cross-country route up the creek above Nelson Lake and over to Tuolumne Pass is very easy and scenic - I wrote up a complete description in the Cross-Country Passes forum here on HST (search for "Rafferty Pass").
As you descend Lewis Creek, stay on your main route (red) up onto the High Trail. This is far more scenic that dropping down to Merced Lake and back up the Merced River, with outstanding views of the entire Clark Range. Once you reach the Lyell Fork of the Merced, leave the trail and head cross-country up the north bank about a mile to camp at the edge of a beautiful meadow with views of the big peaks above. See my trip writeup for the route and photos at
viewtopic.php?t=15812
Beyond the Lyell Fork Merced, the High Trail climbs back up and then runs through the forest, with some views, to the Isberg Pass trail junction. Be sure to take the very short side hike up to Lake 10005 set in its huge expansive meadow with good camping. If you have more time, you can also leave the High Trail near Foerster Lake (just north of Foerster Creek) and head cross-country on easy terrain to that lake, then up the creek valley to marvelous Harriet Lake set on a wide flowery meadowy plateau, and then continue south through more easy terrain past the string of lakes on the north slopes of Long Mountain and Isberg Peak, dropping down the wide valley west of Lake 10217 to rejoin the High Trail.
I haven't hiked over Red Peak Pass or down Illilouette Creek, so I can't advise on that section. However, if you are wearing out or weather is really bad up high, you can quickly run down the trail along the Merced River all the way to Yosemite Valley. I think the scenery is better up high, but the River and its canyon have their charms, too.
If you really want to summit Clouds Rest, I wouldn't add it on to this big loop starting from Little Yosemite Valley. You can do it as a long day hike from Tenaya Lake. Or you can change your big loop to add Clouds Rest if you can get a permit to start backpacking at Tenaya Lake heading to Sunrise Lakes (more in demand than Nelson Lake). Run up to the lakes and set up camp (I liked the outlet area of the middle lake just below the trail) and then do Clouds Rest without your pack as a day hike from camp. Heat east on trail to Sunrise Meadow and then on the trail heading down the Cathedral Fork of Echo Creek. Leave that trail before reaching the creek, at about 9200 feet, and head cross-country up the valley to the east, mostly in forest, to reach stunning Matthes Lake. You can then continue cross-country beyond Matthes Lake to Nelson Lake and do the rest of your loop as planned all the way to Yosemite Valley. For photos and route from Matthes Lake to Nelson Lake, see my trip report at
viewtopic.php?t=22067 .
Have a great time!
-Phil
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