The best chicken skin comes from starting with dry chicken skin. It doesn't matter if your cooking at 250 or 350 degrees... if you start with dry skin and leave it skin side up, you'll end up with crispy skin.
I normally cook wings or whole bird when smoking chicken, and I personally brine all of my chicken (unless it's boneless, skinless breasts) to flavor the chicken and keep it moist... and that way I don't have to apply much rub (usually just sprinkle salt, pepper and chinese 5 spice on my wings). Regardless of brining, you'll always want to pat the skin dry and keep skin side up when smoking (if grilling over direct heat you can go skin side down). And if you're going to apply a glaze or a sauce, let it cook for a while to crisp up the skin before applying anything... applying liquid too early will cause the skin to steam, which causes the rubbery texture.