The grass is always greener. For every person who wakes up one day to realize that they have built nothing in their lives, there's someone else who wonders what they could have accomplished if they hadn't settled down so early. Both of these thoughts are ultimately unproductive. Choose the life that's right for you and enjoy it as much as you can. No one ever looked back and said "I wish I'd spent more time sitting on the fence while trying to decide what to do."

In regards to the first part of your comment, I can't imagine travelling the world with a significant other and children. Perhaps in rare cases for a limited time, but it's hard to imagine that two people would want to participate in that lifestyle for the same length of time. It seems like part of the ethos of "travel" is a certain kind of freedom. Part of starting a family is responsibility, which is the opposite of freedom. Maybe the travelling family lifestyle will become more common as the world becomes more interconnected through technology, but that seems like that could still be awhile away.

Best of luck in your pursuit of the ideal life for you.