I love collars! I use wide, padded, leather martingales or limited slips. A couple great brands are Hamilton Hounds and Sexy Beast Collars (pictured on all 3 dogs below). They are soft leather and come in 1-2 inch wide styles, even in Basenji size. Martingale or limited slip styles are great as they prevent the dog from "backing out" of a collar while walking. It will tighten to the exact width of the neck so it can't slip off over the ears, but does not tighten enough to choke the dog.
Harnesses, although convenient, can be damaging to a dogs ligaments and structure as they twist the shoulder and upper arm ligaments and muscles. Also, harnesses encourage a dog to pull, rather than learning to a walk on a loose lead.