Try Otis Adelbert Kline's two Mars books ("Swordsman of Mars" and "Outlaws of Mars". Published during the time frame you refer to. Main character very John Carter, except that he makes errors in judgment, such as killing the princess's pet because he thinks it is a ravening monster. Fun ERB-pastiches.
Another possibility is Michael Moorcock's "Kane of Mars" series (published under the pseudonym of Edward P. Bradbury). The evil antagonists are the winged First Masters, which fits your requirement. The series was published back in the day by Lancer, instead of Ace, but they may fit. Moorcock's protagonists are rarely likable - Michael Kane is arrogant. He is also "mighty-thewed", a warrior and a physicist (hey, its pulp!). The books are pretty much John Carter ripoffs, although they become darker as the series progresses.