Although group hikes can be a great way to get to know a number of people very quickly, and are by far the wildest of times, it seems to me the fewer the number, the purer the experience.
Two is a great number, efficient, quiet, balanced conversation and shared memories.
Solo trips, particularly the stretches when no others are encountered, can be intensely spiritual. My most recent trip, 34 miles to the bottom and along the Tonto trail of the Grand Canyon, was a life unto itself. The silence and scale very much like what many seek in church. I hope to return soon.
For now, I continue to bag peaks and explore around Phoenix, mostly solo, almost always offtrail. I always leave a note with destination, often GPS info, and am fairly well prepared. Life involves some risk, and hiking solo, away from the dangers presented by others, whether it be rockfall dislodged overhead or a drunk driver, puts the responsibility on the individual.
Reality and perfection are synonymous - Spinoza