DS9 definitely aged better than TNG. The great episodes are still great but the mediocre to okay episodes are harder to watch than the mediocre to okay episodes of DS9.
If Sisko had dated a white woman the show would have faced criticism for whitewashing black characters and been accused of tokenism. If he'd dated an alien they would have focused on the race of the actress cast. The only way to win is if he'd dated an Arabic woman or something.
Well, since some Arabs are considered 'white' by some who want to put people in a box, there probably would have still been people losing sleep because a handsome black man is opposite a hypothetical non-black attractive actress.
I think if Sisko had dated an Asian, Arab, white female and he was allowed to be a strong character, there shouldn't have been any issue. (Again, no one made a big deal about Colm Meaney and Rosalind Chao getting together - but because of racial standards in America, and the thought by some that Asian women are 'white male property,' that's expected).