I think you can tour with others perfectly happily if you want to. I think the key is being on the exact same page and lots of communication. I recently did a tour with my best friend of many, many years. It was great, and I'm glad we did it together, but he's Terrible at communication and I'm not exactly a shining example of communication myself, so there were some frustrating times on that trip. That said, if we tour again, I'll know what to expect on his end, and hopefully there will be more communication on his part too, and everything would be just great the whole trip.

I haven't done any long solo tours, so I'm not sure exactly how things would go in the long run, but my shorter 3-4 day solo trips have been fun. As long as you don't mind the solitude in camp in the evenings, it's nice to be on your own schedule doing exactly what you feel like 100% of the time. I haven't minded that camp solitude on shorter tours, but I could see it getting a bit lonely at times on an extended trip of more than a couple weeks. It may not, though.

I don't think I'd ever go with a touring partner that I didn't know ahead of time unless there was a blunt, plainly spoken agreement that we may well split up if either of us decides and it's no big deal. I wouldn't want to get stuck in a frustrating situation putting up with someone that I didn't enjoy touring with, and an awkward conversation about splitting up.