The Nova Force is based on gravity and utilizes it's powers in the form of powerful gravimetric beams and blasts. Also because of this, Nova is referred to as the "Human Rocket" and can travel and great speeds with great accuracy and maneuverability. His strength is also enhanced and the Nova Force protects him to some degree against energy and radiation attacks. He can also open stargates for faster travel across the universe.
The more Nova Force you have, the more powerful you are. There are still levels of the Corps, and depending on the rank you have, the more power you are given. The Nova Force is immensly powerful on it's own, so Richard doesn't give up what I would call the majority to other members, specifically since there are so few after Annihilation. Richard is the Nova Prime, giving him more Nova Force than any other.
Worldmind is the collection of all intelligence and culture of the Xandarians. It's basically a sentient computer program with vast knowledge. Every member of the Nova Corps has the Worlmind as a resource, but only Nova Prime carries the actual programming of the Worldmind with him to protect it (after destruction of Xandar).
@Emperor Gonzo Noir: I understand that, and I see how it is possible to use each gem individually, but my question is : Why the Gauntlet? The gems shouldn't work together.
@warlock360: The Fault? I don't think that would change anything. An LT has power in all realities, as there is only one LT. His judgment shouldn't be affected, specifically since other Infinity Gauntlets from other realities still obtain their power.