Personally, I see each trait as being two sided. It can have a positive expression or a negative one, and you have to look at which one is predominate.
E.g. someone who is impulsive may be considered reckless in one situation, but also be considered bold in another situation. (and here you can see why "bold" does not necessary mean confident, it can but not always)
Or like someone who is intelligent. Sometimes too much intelligence can cause just as many problems as it solves, it just tends to be in different areas.
I see the same thing with dominance, some people are just more naturally inclined to be that way and it just depends on whether the majority of the expression of that trait is in a positive or negative manner.
I largely see the positive side of dominance as leadership / dominance / decision making.
He may make the decisions but you have the choice to follow what he has chosen. The best leaders do not "force" their leadership on others, others choose to follow them. Someone who is following always has the option to refuse to follow. With that leadership also comes a certain amount of responsibility as well.
For someone like me who is naturally indecisive, it is extremely helpful and attractive to have someone to take the lead and make decisions. It's not that I can't make decisions, or that I can't lead. It just becomes tiring doing it all the time (in work and all the other areas of my life) and I don't want to have to worry about that sort of thing when I am dating a guy. When I am dating a guy I have enough decisions to make, after the date, I don't want to be worrying about the ones I have to make on the date at the time too.
I would not date a guy who had dominance predominately expressed in the negative way. It is not something I would allow or follow. I don't like people who are too controlling or force their decisions on me when i have already objected to them (which is what I would consider the negative expression to be).
When I say I like dominant men, I mean I like those who have the positive expression of the trait.