Make it personal by choosing Hebrew quotes for your ketubah
Beyond, "I am my Beloved's and my Beloved is mine"
By now, you've shopped around and you've encountered, "I am my Beloved's and my Beloved is mine." On the one hand, it is a classic theme for Jewish weddings for a reason - its symmetry, sentiment, and history are appealing and reassuring. On the other, it is everywhere. For couples wanting something just a little bit different, its ubiquitousness may make it much feel less theirs.
Part 1 offers some traditional alternatives. Part 2 will offer some less traditional, but inspiring options.
Part 1 - Traditional Themes
Unquestionably authentic and part of Jewish traditions for many centuries.
Because of the gender specificity of Hebrew and biblical quotes, these themes should be carefully chosen. Because they are biblical quotes, changing them to suit gender is not entirely consistent with Jewish tradition (but that's a whole other can of worms).
He found a woman, he found goodness - מָצָא אִשָּׁה, מָצָא טוֹב
A look at historical ketubot shows that I am Beloved's ascendancy is relatively recent. For many centuries, the phrase everyone wanted was מָצָא אִשָּׁה, מָצָא טוֹב. The whole phrase is from Proverbs 18:
מָצָא אִשָּׁה, מָצָא טוֹב; וַיָּפֶק רָצוֹן, מֵיְהוָה
He who finds a wife finds a great good, and obtains favor of the LORD.
Literally the translation is "He found a woman, He found good and then dispensed with desire, from God." Basically the idea is that once a man is married, he finds happiness, and stops wasting time with unfulfilled desire. This earthy sentiment is at the heart of Jewish traditional marriage. Being married is good for the body and soul and allows one to pay attention to more important things.
Betroth Me Forever - ארשתיך לי לעולם
וארשתיך לי לעולם וארשתיך לי בצדק ובמשפט ובחסד וברחמים׃
Betroth me forever, betroth me in righteousness, in judgement, kindness, and compassion Hosea 2:19
A favorite of couples with a passion for social justice, it is a lovely theme to begin a marriage.
I have found my Soul's delight - מצאתי את שאהבה נפשי
More than any other traditional wedding phrase, this one difficult to translate. Experts disagree because of the poetic phrasing. It is variously said to be "I have found my soul's delight," "Through Love, I found my soul," "I have found my heart's companion," "I found my soul's love," "I found my soul and it is love."
Whichever translation you settle on, the words are beautiful! It also happens to be gender unspecific, leaving it open to all couples.