Being a PK (that’s preacher’s kid), I’ve heard them all. Everything from couples pleading wth my mom, ‘please tell us what to say,’ to pages of sappy doggerel that my mom could not convince them not to use. And I mean PAGES. Per spouse. And my mom had to coach a few of those through endless minutes of vows per person. She recommends listening to the officiant if they suggest an edit…
Some of the ones that were fully hand written (rather than modified for personal use from a more standard form) were fine or even stunningly beautiful and perfect, but many were cringe-inducing on first try. My mom offered to help edit/rewrite some (she’s a decent writer, fortunately), or offered tips on how to simplify for others. Eventually most people came up with something pretty nice even if the starting point was … um… questionable. (She met with a lot of couples in our house, which is how I came to overhear some of these - plus they were often so proud of them they asked me to read them, too! AHHHH!)
So, my advice?
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Ask the officiant for some guidelines - there are legal requirements for the vows, did you know that? You have to identify yourself by name, you may have to identify your proposed spouse by name, and you have to agree out loud to the marriage. Other than that, pretty much anything is possible. But check the local rules, they vary by state.
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Stick with simple. Fewer loopholes, and fewer explicit things you might regret later (“I promise to bring you hot Kona coffee in bed every morning for the rest of our lives” was actually in one of the vows sets I overheard… AHHHH!). Avoid long poetic descriptions of each other’s salient features, of your physical reactions when you see each other, and so forth.
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Go for ideals. Don’t get bogged down in what you anticipate to be true. You are making a vow - a promise of intent. It isn’t a love letter or a description of why, exactly, you want to marry each other. Skip the ‘because your eyes are so beautiful’ parts, and just go for the glory - the highest of what you aspire to promise each other, in the simplest and most direct of terms. Yeah, many people fall short in reality, but that doesn’t mean you should set out planning to fall short. Skip the ‘while love lasts’ and ‘so long as you remain faithful’ and go for the lifetime commitment to your highest marital goals with everything you’ve got. I suspect you won’t have a problem with the ‘life’ thing, but just thought I’d be specific. Defining the highest-level goals can be tricky, but it is a nice exercise.
I like the Quaker vows, myself. We customized slightly (using Divine/Spirit instead of God), but otherwise, kept to form. Much easier to memorize if they are short. And with Quaker weddings, you don’t have a choice on memorizing - no minister to prompt you if you forget. Mine:
“In the presence of the Spirit, and these our friends, I take thee, <name> to be my husband, promising with Divine assistance to be unto thee a loving and faithful wife so long as we both shall live.”
We also added something about the rings, along the lines of “I give thee this ring as a symbol of my vow” - and added what the rings were engraved with. But that part was less important, in my mind, than the vows themselves.
Loving and faithful covers everything you can think of that you want to promise, or at least everything I can think of, which is why I like it. Can you think of anything that doesn’t fit? Anything else you want to add or elaborate on you can put in a reading elsewhere in the ceremony. People can be moved by it, and will not wonder what you were thinking including that in your vows. Just in case Eve is coming to the wedding, you know (in the form of a grandmother, say). 
I also like a set of old Scottish vows I ran across when I was researching possibilities for ours (from about 1200 AD?), but they might be a bit much: He: I promise to worship you with my body. She: I promise to be bonny and buxom in bed and at board. According to the source, the text was a church record, and in the margins a priest (presumably) had noted that ‘bonny and buxom’ was local dialect for ‘chaste and obedient’… yeah, whatever they told you, Father.