The Organians appeared to be human, but they were eventually revealed to be beings of pure energy. The extent of their powers is unclear, but they were able to prevent the crews of both Federation and Klingon warships from operating their consoles, thereby preventing a battle between two fleets.
The Organians appear to be loosely organized. They have a single leader to speak for them, but he appears to be nothing more than a spokesperson. Whether the Organians have a political structure as we would understand it is unknown.
The Organians appear to possess great power which is presumably inherent to their energy-based physiology. They could presumably overcome any of the major powers in the Alpha Quadrant if they chose to do so, but they have no apparent interest in conquest. As staunch pacifists, they are not even dangerous to invaders, although they might use their powers to disarm antagonists if sufficiently motivated.