There is not a hard and fast rule. I think what I like and why their vaginas are often tight is their age rather than their race. But I do love their tiny butts and waists. Also, some of the smallest women have no difficulty with the length of my cock, whereas others do, and I'm only 3/4 or less of the way in before I bottom out.
Honestly, I don't care either way too much as long as they, as well as I, enjoy ourselves.
Some of them can't wait to get me in their pussy and I have to slow them down whereas others are really wary and ask me to be careful which, of course, I am. Viva la difference