It's far more important to me what is on the inside than the outside of a woman. In fact, I've met very few traditionally beautiful women who had personalities I admired. Society treats people differently based on looks, and it spoils beautiful women to such an extent that it's the hard not to give in to this.
A less traditionally beautiful women cannot depend on her looks, and thus gravitates toward nice behavior almost subconsciously.
Yes, I know, those are gross generalizations, and I've met quite a few exceptions to those rules, in both cases, so don't bother providing anecdotal evidence about this genuinely nice beautiful woman or this horrible ugly woman -- I know.
More to the point of the question, I prefer the inner beauty because after you have been with a person for a while, you stop noticing their looks for the most part. You don't see "a beautiful woman," you see "my partner." Meanwhile, their inner beauty shines through day after day.
Having said that, I have been conditioned by society enough to be affected by physical beauty, sad to say, so I often succumb to the charms of outer beauty before noticing their inner qualities. Not proud of it, but I admit it. To my credit, inner beauty always wins the day eventually. But I wish it didn't have to take time. Being online helps, as I get to know the inner person first.
One last confession, and one I'm not at all proud about, nor do I have any idea where it comes from: I am not attracted to women who are more than a little overweight. A little? OK. More than that? Nope. Shallow? Absolutely. Wrong? Yes. Built-in to me? Sure is. Why? I have no clue, but it's very deeply built in and seems to have always been there since childhood. It could be, I'm guessing, that I come from an extended family where no one is overweight, so perhaps as a child all I ever saw as models of body types were either slender or, at most, middle-aged slightly overweight. Whatever the cause of it, I find it hard to be physically attracted to such a woman, no matter how much I admire their inner beauty. As I said, I'm not proud of it, but there it is.