DMC was influenced by games and gathered elements to create a new idea like u said.....and god of war was influenced by games including DMC and added few new ideas which in turn influenced succeeding games....so its a loop
and as long as the game doesnt heavily rely on another game's idea(ripping it off) there is nothin wrong with it :)
IMO DMC is the inspiration of H&S and GoW is the best and most successful