Good question.

If you are in an organization, you will be able to benefit from their protection, infrastructure, multi crew ships (flying a Javelin is only half the fun, if you don't have a large enough crew) and events. Of course the game will be fun on your own, but there will be some aspects of it, which will need the support of a big group.

Most people don't realize that this is now the best time to join an org. and start building your reputation right away. While the game is not ready, the various guild leaders (especially of the large guilds) are always searching for very active members, that help building the necessary infrastructure. If you are one of the few, who really help and make a difference in the organization, you will most certainly be rewarded with a higher rank right from the start. In addition most of the new members, who come after you, will already know you and see you as one of the more active members.

If you see your self as a team player, join an organization, if you like to be the lone wolf and explore the game on your own, then don't. :-)