To me, the only offensive thing about what she said is that it implies Christians are perfect, when, in fact, all people, Christian and Jew and otherwise are imperfect. But I do agree that Christ is the "perfecter of our faith" and, therefore, Jews and others can only perfect their faith in Him.
I recommend people watch the video of the entire interview rather than read snippets and talking points. The context is important here. The host badgered her over and over going from one topic to another to find something to be offended by, and eventually went to that old fall-back religion, taking something she said in the middle of a larger statement to focus on.
Imo, It is not a reasonable response to be offended when someone wants, in love, for you to understand the Source of all love, forgiveness, salvation, hope, power, and glory in the universe, especially when that Source has been what your religion has sought and yearned for for 4,000 + years. We are not talking about forced conversion or death, Muslim style, nor conversion by the false claim that you-can-continue-to-believe-what-you-want-only-add-our-beliefs-to-it, as the Catholic church does. Messianic Jews are as much Jew as Christian but have found the "author and perfecter" of their faith.