I dislike Kennedy as it is, but this spelling doesn't make it any better. Kennedi looks quite juvenile and the I ending makes it look even stripper-ish, like with Brandi, Misti, Averi, etc.
KennediI named my daughter Kennedi, I wanted something strong, something unique, and something Irish. Why I landed on Kennedy it was because of JFK and to make it a bit more personal we opted out for the EDY and changed to EDI to make it her own and unique. My little one is 8 right now and she's a strong ,independent, sassy, outspoken and a kind-hearted little lady.