I haven't defined it exactly. I suppose a good place to start would be countries that have democratic elections. The only country I have visited in my life that didn't was Lesotho and that was just for a couple of days during a trip to South Africa.
As you say though, it's not black and white, but Dubai sits pretty comfortably on the wrong side of that line for me.
(I'm talking about holidays strictly here, rather than other reasons which might have other justifications).
I understand what you're saying but no. I want to see the whole world if I can and I happen to be alive now. I can't wait till some countries or parts of the world change for the better, which may or may not happen in my lifetime, if at all. I have to deal with the here and now.
And besides, the people in badly run countries are often much more likely to be victims of their governments than complicit.
Everywhere I've travelled to, no matter how 'unethical' or dislikeable the country might be, I've met great people, real, genuine people who don't represent any of the things I might disapprove of, or who are hungry for change and looking for hope. Or who may well represent certain dislikeable attitudes but only because they've never known any different. That's who I go for, not the governments.
And without sounding overbearing about it, wherever we go we can take a little of what is best about where we come from - ideas, attitudes etc - with us. God knows there's enough shite in our own western countries, but what good there is we can try and exemplify it. That's one way that good attitudes and ideas will spread, over time.
Bad places aren't going to get better if we turn our backs on them and let them fester. Be the change we want to see in the world, and take it with us as we engage and build bridges. And of course, there's plenty we can learn as well.