Taper, is one preference folks will point out. Diameter at the tip is another. For me, the collar style (both my Joss cues have dashed rings, which you don't find at various websites).
I've shot with many weight cues. My Meucci is an 18oz, 12mm shaft cue. My first Joss I asked for a 21 oz 12.5mm shaft because I hadn't measure the Meucci shaft. I prefer a 19, 19.5 oz cue, and will adjust to the 12.5mm. My cue being built is going to be between 19.25-19.5oz 12.5mm. I don't...