I did a one day solo trip in August and it was so fun! I walked about 15 miles, sweat pouring down my back and my feet were killing me and I didn't even care. I got the
lightning lane multipass for the day, set up my preset rides for Epcot, choosing to take advantage of short rope drop lines at Hollywood Studios. I rope dropped Hollywood Studios, did my top choice rides, got out early because Rise of the Resistance was down. Took the Skyway to Epcot, did my top choices there then went to Magic Kingdom where I spent the rest of the day, doing whatever I wanted and chasing lightning lanes. I used the customizable touring plans app to find short lines, crisscrossing the park willy nilly without anyone complaining, I wore Archie's flip flops and quick dry clothing so the afternoon rain wasn't a problem. Ate whenever I wanted, used the bathroom as often as I wanted, brought back small treats for my family to assuage some of the guilt

Very few rides had single rider lines but I took advantage of them where available.