solo and CHILD-FREE
Something I cannot speak for as a traveler is being a parent. I don't have kids: hence, I feel authorized to speak on “solo travel” versus any kind of “family travel” (honestly, when you are a child-free adult, the world of parenting can be a bigger “culture shock” than any exotic land you could visit...)
So, I would not take it upon myself to speak on the logistics, the financials and the psychology of traveling with kids. I've seen it done successfully and I've seen it done badly (one of the key take-aways so far is: traveling abroad with children requires a "decent" budget as opposed to a "shoestring" one).
Here's what I know: in all my years of backpacking around the world, staying in hostels and occasionally waking up in unfamiliar crash pads, there was not a single instance when I thought to myself: “What I'm really missing right now is an infant / toddler / tween to make things more interesting and meaningful!” Nah-huh. I was always quite consciously relieved that there were no extra responsibilities to worry about on the spot other than my own immediate needs and safety. No doubt, family travel can be rewarding in its own right, but this particular guidebook is all about prioritizing one's autonomy and traveling for oneself on one's own terms.