Difference between Luffy and Enel is that Enel can be hurt by rubber and only rubber because of his devil fruit(that and the obvious devil fruit weaknesses) while Luffy's devil fruit power does not make him extra weak to cutting or cause him to be cut. It's just it doesn't protect him against it but it doesn't neutralise it or make it weaker. That's why I don't think Mr.1 is Luffy's natural enemy.
And I think people are getting a wrong impression of Mr.1's ability. He wasn't a blade man if I recorrect but a steel man. In other words punching him in the gut won't slice Luffy's hand as long as he didn't already form the blades. Luffy's not an idiot when it comes to fighting. He's a combat genius so I'm sure he could have adapted his strategy if ever paired up against Mr.1.