Was Boromir a mistake?

I can't say that Bromir having gone was a mistake, but it sure had some drastic consequences. And Faramir may seem as a greater man then Boromir, but he was still "a man" (a human), which means to me that he had the same weaknesses Boromir had, but under the disguise of another personality.

And Boromir spent a long time and went through several events with the "company" of the One Ring. The One Ring had plenty of time to act over Boromir's mind and will, which were weakened by the sad turn of events, and influence him in ill ways. Had Faramir been the one to join the fellowship, the One Ring would have still had time to influence him and act over his mind.

I don't know if this is a satisfactory answer, but this is what comes to my mind at this time.