The marriage at best should show only razor thin lines at the glue joint. Often the marriage is at an angle, if it is, the best rule of thumb is that the angle of the joint should be lined up with the nose of the head (the outer curl),
and the nose should generally be slightly above the position of the joint. If there is an accent wafer it should be of an appropriate thickness for the overall bulk of the stick. Thin sticks of pale wood, such as holly, or hawthorn might need no more than a sixteenth inch sterling silver band, where a heavier stick of hazelnut or bark-on cherry might need three eighths inch of African pink ivory (a rare, and beautiful wood). If the head is rams horn, often it looks best with nothing at all at the joint. If Chinese water buffalo is used on a shank of perhaps flamed ash, because both the head and shank are very dark, a slice of cream colored stag horn might look best.
The marriage also should be straight, sight down the stick from the end and the head should not sag. If anything the stick as a whole should have a very slight curve away from the nose, so if you put pressure down on the handle, it will straighten out.
Today I think that the best sticks have steel pins glued in the joint for strength. ¼ or 5/16" pins are best, and although allthread is ok, drill rod from the tool and die makers is the best, It allows the fitting of the marriage very accurately before it is glued up. You often still find imported sticks that are pegged, which means, there is a large hole bored in the handle and the shank cut down to fit. The strength of the shank is, of course, determined by its weakest point so they often break right at the joint. To compensate for this weakness, there is often installed what is called a ferrule, or collar as a decorative band that covers the joint, and to strengthen it. These are most often made of horn that is stretched while hot, and then shrunk on again over the joint with heat. It is then carved in some pattern, or just smoothed, and polished. These decorative bands do remarkably strengthen pegged sticks.