Aes Sedai take it very, very slowly. It seems common for sisters not to have reached their full potential by the time they gain the shawl. The Aes Sedai have an innate fear of the seduction of saidar, they don't encourage any heavy channeling early on, working on building strength of will of the women first.
The sul'dam rather train damane intensively and daily. They mean them to gain their full strength as fast as possible.
Egwene then went on to channel as you'd expect from an Aes Sedai, not a novice or Accepted. She finished to gain her strength fairly rapidly. So do Elayne and Nynaeve who progressed much faster than if they had been in TV, but unlike Egwene they have not been forced, so they were still quite a few levels below their potential when the series ended (Nynaeve less so than Elayne, who probably halted her progress since her pregnancy).
