Context for the quote.
I think you're misreading Jimenez here. I see several possible readings through which one can understand Jimenez's take.
The first is to look at the items symbolically. The sword is a symbol of war and violence, but even more it is a symbol of authority. Not justice as in making just decisions, but justice as in the wielder having the right to make decisions. That's a symbology that's rather far removed from Diana, who is here to stop wars through love and helping other people reach just decisions.
The rope, on the other hand, is not as overloaded symbolically as the sword, but it's really more interesting. It's a symbol of the executioner (via hanging; but so can the sword be used), it's a symbol of bondage, but it's also a tool that connects things and can save lives. It's no surprise that many marriage ceremonies include ropes as part of the ritual. I think that duality is something that can and should be explored further in Wonder Woman.
Now, looking at the Magic Lasso, it is a rope with all the powers that you mention. In many ways it's one of the most overpowered items in the DCU. But it's still symbolically a rope. Also, one of the more interesting aspects with Marston, and which some other writers also have latched onto, is that Diana is extremely careful in using it against other people. She readily catches things in it, but she seldom ties people up in it (in Marston's run, I think the most likely person to be tied up in it was Diana herself), and when she does so it is in order to reach further understanding of them. So at the core of Diana's use of the Magic Lasso lies—IMO—the idea of responsible use and reaching understanding between people. Or in the end the ability to reach just decisions by unmasking the truth. But even there, the Magic Lasso is just a tool to reach the truth, and the truth is still only a stepping stone to the goal of reaching a just decision.
In comparison, when the sword is present, Diana seldom shows any hesitancy about using it.