{Novice}: just getting started, just using weapon with brute force.
.
{Intermidiate}: the user could control their weapon like an extension of their body. user could also use some technique.
(like the technique zoro use at his fights before alabasta arc)
.
{Master}: the user could already used aura as a mixture with technique they mastered.
(like zoro when he cut pica)
.
{GrandMaster}: reaching this level boost the user strength by a huge margin, they could already send out aura with just one normal swing, but using it with techniques and styles, it became much more lethal and deadlier.