Your list looks very solid. Here are the only suggestions I have:
1) Lose the extra t-shirt and embrace the filth.
2) Try packing without using the stuff sacks. At 19oz, I'm assuming your backpack is the Arc Blast 60, so you should have plenty of room without the marginal amount of compression the sacks offer. Your pack liner will keep your clothes dry.
3) Use a stake for digging your cat holes so you can ditch the trowel.
4) Especially for summer trips, consider going stoveless. Sure, it's nice to have warm food when it's near freezing at night, but during the summer I've found it's not worth the hassle when you're exhausted after a long day of hiking. It's pretty easy to find no-cook backpacking meal ideas online.
Also, if you have the time, could you shoot me an email at jvance08(at)gmail(dot)com? I'd like to pick your brain about two things: (1) I'm applying to medical school right now, so I'm curious how backpacking fits into the life of a physician, especially during the training years and (2) I have a trip planned to western NC at the end of the month, so I'd love any suggestions you have for must-hit trails. Thanks!