Curiosity, when he was alive, I don’t think his chassidim’s wives visited him on Rosh Hashana. He wanted the husbands to instruct their wives in chassidus. This is explained on the website I previously quoted from.
Regardless, your argument doesn’t work. Gedolei Breslov, not Litvishe and Sephardi poskim, are the ones Breslov chassidim should listen to, regarding how and whether to follow Breslov minhagim. If it were otherwise, Breslov chassidus (and for that matter all the other streams of chassidus) would not exist.
Rebbe Nachman believed in following the Shulchan Aruch, and criticized other chassidim for not following it (such as those who davened after zman tefilah). He also spoke strongly against unnecessary chumros. The Shulchan Aruch does not say men should always be with their families on Rosh Hashana.
In any event, it makes no sense for non-Breslovers to come forward and say, but Rebbe Nachman would have wanted you to do X, not Y. Breslov traditions have been passed down faithfully from generation to generation, and the leaders of each generation of Breslov chassidim are necessarily empowered to determine how minhagim are to be followed.
I personally think it would be nice if women and children could come with their wives to Uman on Rosh Hashana, but 1) the presence of large amounts of women and men together in the same place would be unacceptable because of tznius, and 2) who am I to argue with the consensus of gedolei Breslov?