This is my opinion on the roles in the JT.

The Dancer
The Dancer is a female who was given dancing talent by the moon. There is one in each generation- Victoria, Bombalurina and Jennyanydots. The kitten one is given the spotlight during the ball, the queen is given a solo in the tom-fight, and the senior is given a dance song. They are usually the most popular female of their generation, and are often flirted with. They are chosen by the Everlasting Cat on the The Choosing Moon. They are commonly an outstanding colour, and without scruffy legs. They must dance at most Jellicle celebrations, and be the first to courtship dance.

The Trainees
The Trainees are the tom-kittens, who are training to be soldiers. They are Plato, Pouncival, Quaxo and Tumblebrutus. Out of these, one will become the Sentinel when they fully grow, and they are given lessons by the Sentinel and his soliders. They are usually still small and cheeky, and like to flirt with the soldiers mates. All tom-kittens have this role, but not all of them become soldiers. They are mostly still scruffy-legged and young-looking, with some white on their torso. They must obey the soldiers, and be willing to fight when needed.

The Psychics
The Psychics are cats of any age with a heightened sixth sense given by the moon. They are Coricopat and Tantomile, who are twins, and Mr. Mistoffelees and Jemima, because they all have magical talents that they use for good. They are heralded and praised, and help eachother perform miracles. They often court eachother, because they are all so pure and kind, yet still have a sense of humour. They all discover their talents as they grow up, and are often presented by a full-grown to the rest of the tribe. They all are mostly black and white, and must help the tribe and others whenever they can.

The Railway Cat
The Railway Cat is a senior of any gender who helps at a railway or station. He is Skimbleshanks, who is a senior. He receives a song inhis honour at the ball, and help the soldiers to protect the tribe, as he is physically fit.