I wouldn't change much, but here it is off the top of my head:
- I would probably skip all the camping gear. Setting up camp at sundown and breaking it in the morning is not for me if I want to enjoy a good long day of riding. Camping and riding can be mixed very well, but only if I set up base somewhere for a few days and ride in the area. It's just my preference, of course.
- There were a few pieces of clothing I didn't use for the entire trip, so they'd be gone next time. Shoes are a pain to pack, so I'll pick them more carefully. Also, a pair of jeans to replace my Carhartts at the end of the day are enough - no need for another pair. Shorts that can serve as swimwear.
- I didn't bring any underwear or t shirts made of cotton and that was a good decision. CoolMax, microfiber and other fine artificial materials rule. They wick moisture well, are very comfortable and warm in colder weather, dry fast and are easy to wash. No leather except for boots and gloves.
- Speaking of gloves, gauntlets are a pain to take off and put on when they are sweaty. I ended up wearing my short gloves the entire trip. I always tighten the Velcro on my jacket sleeves well, so I consider it an acceptable safety tradeoff.
- I'd upgrade my tool kit a little. I was more than well equipped, but still ended up having to buy a couple of wrenches.
- I'll definitely come better equipped for recording next time. Bike or helmet mounted photo camera with GPS and a remote trigger is a must. A way to do voice recording while riding is next. I missed so many beautiful vistas and forgot too many interesting events. Descriptions I was coming up with while riding beat anything I wrote by memory and after the fact.
- I'll plan a little better. Not too extensively, but just to make sure I don't pass by something interesting because I didn't know it was there. A small-ish laptop with info on good motorcycle roads, places to stay, etc.
- I was fine with Sena communicator and Verizon prepaid phone, but there's room for improvement there.
- I'll pay more attention to chain maintenance. Or buy a shaft drive bike

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- Maybe upgrade my tank bag. It proved he most important of all luggage I had because it is most versatile. It held my hydration pack, snacks and visor cleaning microfiber sponge among other things. I'd like one that's easier to put on/off and move when putting gas in, but the one I have did a very good job.
Since you'll be riding solo on an SS maybe you can consider something like a waterproof gym/hockey bag to stretch over your rear seat. Tank bag is very important too. I'd forget about backpacks - too clumsy to put on/off all the time. Soft side bags are OK, but make sure they are mounted securely. Most of all, make sure you can take a long ride on a bike that's not really designed for sport touring or shorten your days accordingly.