Right on for your hike on the PCT. You'll love it!
You've got a good list going. Some specific comments:
You might want a warmer bag for parts of the trail. I used a 20 degree WM bag (Alpinlite) for everything except Tahoe to Ashland (used a synthetic 40).
An excellent choice. I have one and love it. However, I used a Squall 1 on the PCT in 2004, and it was nice to have some extra room when the long rainy stretches set in in OR and WA. More room to keep wet stuff wet and dry stuff dry. But the Contrail will be great (if I did the PCT again, I used the Contrail).
Bring a patch kit. There are lots of pokey things in SoCal.
I used the same Tyvek sheet from Idyllwild to Canada. I like Polycryo too, but there's something nice about a tougher groundsheet like Tyvek. You can always dump it down on any surface, for a nap, for overnight, etc. It's heavier, but I think it's worth it for a thru-hike. Make sure to always use the same side down, as it does start to fray a bit and collect weed stickers and such as you go on and the fibers start to wear.
No real thoughts on clothes, other than I carried a set of sleeping long johns and socks the whole way (except Tahoe to Ashland, when I used the 40 degree synthetic bag). Both to keep the expensive down WM bag cleaner, and also since when it's raining and cold, it's nice (and safer!) to have a dry set of clothing to change into at the end of a day spent hiking in the rain. I kept my sleeping clothes in a dry stuff-sack with my sleeping bag.
0.9L pot - perfect size for one hungry hiker.
Esbit is fine (though I have never used it).
Aqua Mira is what I used, though I might go with the tablets instead if I did it again.
Water containers - you'll need between 1L and perhaps 6L. I carried 3-6L for most of it, and only 1L from Kennedy Meadows to Tahoe. You can adjust with a bounce box/resupply box as you go. I'd just carry a couple 1L Aquafina-style bottles and 1-2 2L Platypus bladders, as necessary. There are long stretches in SoCal here and there, and also in Oregon too! You'll quickly learn to camel up and deal with the waterless stretches - it's not a big deal, but take it seriously! (and DON'T rely on the water caches, which are occasionally empty - and SHOULD NOT be maintained, as a side comment in my opinion).
First aid - Take minimal stuff. Ibuprofen, Benadryl, antibiotic packets, duct tape. Not much else (see other threads).
Compass, mirror - Don't need them.
Backup light - Don't need.
Headnet/DEET - Once you hit the mosquitoes, you'll definitely need these.