Been considering cutting usanyp back to just a "select" system, of only routes with shields. That system's been largely on the backburner though.
No rush on responding to this, but are there many that would qualify that aren't already in usasf?
Bear Mountain Parkway, Bethpage State Parkway, Jackie Robinson Parkway, Korean War Veterans Parkway, Loop Parkway, Mosholu Parkway, Niagara Scenic Parkway, Ocean Parkway (Long Island), and Seven Lakes Drive. Wikipedia also shows a shield for the Lake Welch Parkway, but I couldn't find one in street view.