God, I remember that show along with Johnny Socko & His Flying Robot (which was called simply Giant Robo in Japan). They'd air the two shows every other day on local syndicated channel TV 20 in Detroit during the late 1970s-early 1980s, along with the 1960s Spider-Man cartoons and so on. Now if they'd only release Johnny Socko on DVD I can relive those childhood memories in one sitting during the rare days off from work I ever get.
Oh, and I dig your interpretation of Hayata and the Defender from Galaxy M-78 himself. Of course, I've also grown to be a fan of Ultra Seven and Ultraman Ace thanks to the TNT Network and the so-called "bootleg VHS market" of the 1990s.