1/ Whereas, in the US the template was Superman, and thus you got superheroes in costumes, Frew and Australian publishers used the template of the masked mystery man, (yes, definitely the Phantom) so Frew had Phantom Ranger, Sir Falcon and the Shadow and there was also the Panther and the Raven. Then there was Catman and the Crimson Comet.
My point about the same company is that DC/National Publications were very litigious. Their early success with Fox's Wonder Man (only one story published before legal action) lead to an avalanche of legal threats and law suits against the publishers of Steel Sterling, Master Man and, most importantly, Captain Marvel. Interestingly, Will Eisner, who created Wonder Man, agreed he'd been asked to create a Superman-like character but said he'd drawn more on the Phantom than Superman for inspiration.
Catman has some Phantom aspects to him. He's based at Cat Rock (similar to the Skull Cave), and he's assisted by a boy called Kit (which is both the given name of the current (21st) Phantom and of his son).
During some research into the Phantom Ranger, I found the following comment by John Ryan on the Shadow and the Phantom Ranger:
Following the success of The Phantom Ranger Frew Publications introduced The Shadow in May 1950 and continued to publish the title until the middle ’sixties. In portraying Jimmy Gray as a seemingly bored millionaire who is really The Shadow, the comic vied with The Phantom Ranger for its lack of originality.
(p.200,
Panel by Panel) I find this a bit harsh, but Frew were certainly playing things safe in creating new characters. History shows us that the lack of originality in a character concept doesn't preclude good and entertaining reading!