Paisleigh Saige! Super cute!!
I've gone through that as well. All my kids have unique names. I'm stuck on the spelling either way.
Phoenix Sawyer, if only because you will not stick the child with having to spell their name to every comer for the rest of their life. Take it from one who lived it, I had a name that was unusual in the state where I lived and at that time, and I had to spell it out to adults and found it VERY embarrassing, especially to have to do so to a teacher in front of a room full of kids. (I was shy and it made me feel like a freak.) My niece, who was given a "creative, clever" spelling by her mother, legally changed her name in high school, that's how much she liked it.
If you do use Hayleigh or Paisleigh, please consider spelling them a little more like they are usually spelled, they are interesting and distinguished enough as Hayley or Paisley without the added help of the "creative" spelling.
Or, if you are entirely stuck on the leigh part, why not compromise with your significant other and call the child Leigh? (Of course, that doesn't solve the kid-having-to-spell-it-out-all-the-time problem, but at least it's a known name, and is distinguished and interesting, rather than just looking like someone messed around with spelling.)