Spaying for dominance issues alone?

I am a breeder. I have a female that has never bred and is intact. So I started letting her out in the morning and putting her up at night since there is no chance she will breed with a wandering tom. Though her territorial behavior seems to be the same as an intact breeding female. Do you think it is worth spaying her to curtail that dominant behavior?

If you're not planning on breeding her, there's no excuse for not spaying her. And it will even out her personality & make her less likely to stray off with a tom.

"there is no chance she will breed with a wandering tom" is one of the most ridiculous statements I've ever heard.
   
If she is spayed, there is no chance. I personally have never met even an "indoor-only" cat that didn't at one point in its life get out to breed.
   
Do the overpopulated cats a favor and get all of your cats spayed/neutered. Its a lot healthier and cuts down on the 6 million cats the US euthanizes in shelters annually.