The Istari (or at least most of them). I decided not to include the blue wizards in this sketch, perhaps some day I'll do them in a different sketch. Things to remember this is how I imagined Tolkien's wizards from reading the books. I do imagine them all having pointy hats ( this is due to some hinting references of Saruman having one in the Two Towers).
As to the design of they're staves - I took inspiration for the Valar who chose them. to those unacquainted with the Valar lore, they are like gods (little g) or Archangels.
Another note on Gandalf's staff- The Hobbit had a reference in chapter 1 of it having a spike; also Gandalf was heavily inspired by Odin, who carried a spear; Furthermore Gandalf was chosen by the Valar Manwe, and I imagine him also having a spear.