It sounds like you don't like the name 100% but feel obliged to use it. Maybe in that case, you would be able to use it as the middle name and not the first name? Then the spelling wouldn't matter that much.
I am not too big on giving a kid a name that is said in the usual way and trying to make it "clever" or "unique" by changing the spelling. If it has a different pronunciation, that's fine, because the different pronunciation signals that there is also an unusual spelling. But, especially with first names, this creative-spelling thing is hard on kids, and it continues to irritate them throughout their life whenever their name is spelled wrong, which happens (according to my friend Lyndssey) pretty much continually. If someone's name is said as "Laura" but spelled "L'eaureah" or something, it just makes especially school kids feel singled out and self-conscious correcting people all the time, especially since the people in charge of writing it down (and not usually understanding what the kid is saying on first try) are often adults.
Holly in alternate form is Holea or Halig, but I don't think that is going to help you much. lol The beautiful and romantic holly plant has the Latin name of ilex, which in some places would be an OK girl's name. The holly plant grows readily in laurel forest zones, meaning that Holly and Laurel are natural friends. Don't know if any of this helps. I wish you luck.