I think your clothes are well chosen for higher elevations like the Sierra (though a 200wt fleece equivalent may help here), or parts of the Desert Divide, and N. Washington. Its perhaps too much (!) elsewhere.
Think dynamically about your wardrobe, and send things ahead you won't need.
Pants: Personally I would roast without shorts; when I hiked the PCT through Oregon and Washington, even in June, I wore pants only when it was blowing rain or I was not moving (or the mosquitos were buzzing--but then the heat was almost intolerable). I know many people hike in pants all the time, but nothing is as light or freely moving as running shorts. You won't need thermal pants most of the time, probably only in the first few and last few weeks. Figure out your running temperature and then send them ahead---perhaps way ahead to where you'll need them. I don't think you'll need rain pants, even dri-ducks. If you do bring them, save them for September in Washington, not before.
Overmitts are not really necessary for the (absense) rain on the PCT, only for the bugs and sun (OK, maybe your last two weeks in WA); hence eVent mitts not necessary. Just sew some tubes for your hands; they'll work for the sun, too. .1 ounce.
Shirt: I wore a long sleeve shirt for sun-protection, especially when in open country, and there's lots of that on the PCT. I also highly recommend an umbrella. Many people do the PCT without one, of course, but this is one trail where, despite the lack of rain, you can keep nice and cool under its shade in the intense sun. This lets you go shirtless, too, which is oh so comfy. I admit I'm kind of an umbrella evangelist. At least consider carrying one for a while to see if it suits your style. It'd be most useful down south, through the High Sierras, to protect from the intense sun, and then again in WA to protect from the sometimes unceasing drizzle. There are ways of carrying one while using poles. Search the forums.
Poles: A matter of personal preference, of course. But for the PCT, which is never steep, I'd at least recommend sending them ahead for a section or two and see if you really miss them. I'm continually surprised by how many hikers have their poles stowed. And there are always sticks to use for a while.
Gaiters: I know people like them, but I'm not sure how much effort and annoyance they'll really save on the PCT. I'd start caryying them and see how well you do without them.
Cooking: consider a bigger pot, and sharing with your partner (1.5/2L for the two of you). You won't believe how hungry you'll become. If you already have more pots, consider sending a bigger one to pick up in Big Bear, when your appetite really kicks in.
Shelter: Anything will work fine; I used a blue woven poly tarp, 8x10. Not light, but only 4.99. Slept in headnets and bug proof clothing for a few nights.
Pack: Forget the pack cover, carry a garbage sack to line your pack in the slim chance of rain. Replace the sack frequently, as even unused they can develop holes where they're folded up.
Water: You'll need a few liters down south; elsewhere there are only a few places where you need to carry more than 1L of water, which at thru-hiking pace can last ten-15 miles easy. Water sources more than that far apart are few and well noted in the guides. Send the extra bottles ahead to those sections. If I were doing it again I think I'd use a UV purifier and drink a lot at each source. Then you don't have to carry so much while waiting for the treatment to take effect. I didn't filter most of my water, and in high wilderness areas, with no grazing or much horse trafic above, chosing sources carefully, you can get away with it. Just wash your hands after doing your business.
Camera: Consider one that takes AAs. That way you can dispense with the recharging hassle/worries.
Well, that's way too much procrastination. Back to work.