I think the answer is yes and no. To me, I think even non-lucid dreams are fantastic. I've had non-lucids which were really mundane and I've had some that were just terrific, very vivid and with interesting stories. What one needs to remember is that you will always have non-lucid dreams. I haven't heard of anyone who can control ALL their dreams EACH day. A lot of the experienced members on here can become lucid easily, but, their number of non-lucid in total far exceed their lucid amount. Also, even if one is lucid, he can chose to follow the flow of the dream or take his own path learning in the process. Invader's example is perfect for illustrating this point. As to the message of the dream, well, most of my dreams revolve around RL, basically work, school, family, etc.... so I am basically replaying RL in my dreams which makes it hard to pick up a message. At least with some lucids, one can better themselves at a certain subject, practice a sport to get the hang of some move and furthermore, they can experience things that they would never be able to experience IRL and just get the feelings for it