I did a solo three day bikepacking expedition two weekends ago, and came back feeling that I really wouldn't change much. I still need to tweak the way I carry the sleeping bag under the seat, and I forgot a couple of pieces of gear (insect repellent and a head torch), but that was about it.
I have finally gotten to the point where on most tours I discover I'm missing something, rather than bringing anything I don't use. But before that, every successive trip had less stuff than the previous one. On this trip, I didn't even bring pants!
About the only thing I brought on this one that I didn't use was goretex gloves and a rain jacket - because it didn't rain.
Steve