Yes, I already know that you think she is the perfect angel and that she has an invisible halo shining above her head at all times, but this is not the halo I am talking about. Ever think about surrounding a solitaire diamond with small little diamonds? This creates a halo, and can make a ring look bigger. Halos are available on all different diamond shapes, you can even mix shapes. You can have a round center stone with a square halo. It just gives a bit more personalization to the ring. Halo’s have become much more popular over the last 5 years, I myself have a halo engagement ring. It’s up to one’s own preference. I personally think they add more bling to a ring than a simple one stone.
Not only is a halo beneficial because it makes a ring unique, it is good for your ego. You can always be really cheesy and tell her that you picked out a ring with a halo design because she is your angel, or because you know an angel sent her to you.