I dunno. Because of how many factions there are in the series and the number of main characters through whose perspectives we see the story, I think the logical conclusion is that there are no heroes or villains. Will Dany end up being in opposition to other favorite main characters of ours, like Jon, Tyrion, Jaime, Davos, Arya, et al.? If she would, I don't think she should be regarded as a villain, she's just a main character in situational opposition to other characters. Obviously characters like Cersei and Jon are in opposition (seeing as Cersei wants Jon dead), but the rest of the "honorable" or "heroic" characters in the story probably are in questionable relationships with each other because most of them don't know that the other is alive or even exists.

Most of the main characters in Westeros don't know or care about Daenerys because she's so far away and has had absolutely no impact on them (that they know of at least). If she comes to Westeros and plans to conquer it, I would imagine there are a good many characters that wouldn't want that to happen, or at least not in the way she intends (dragons, Unsullied, sellswords, Dothraki, etc.).

We know that House Martell and the Dornish would support Dany's claim, and Doran would go all-in on her since he's got nothing to lose. She cares about people, and she despises slavery and inequality, so in the absence of someone like Margaery the smallfolk would probably love Daenerys; that is, if she doesn't have some revelation while she's with the Dothraki that turns her into a ruthless and/or mad dictator. Either way, the powers that be (Littlefinger, Cersei, the Citadel) may oppose her. Melisandre may think her to be a false Azor Ahai and condemn her. Jon and any remaining Stark loyalists may find her dangerous, being the seed of the king who murdered two Lords Stark (unless Jon figures out that she's his aunt, in which case he might feel compelled to help her).

In any case, Dany's not a hero. She definitely won't end up coming to Westeros in force to conveniently and heroically burn the Boltons, the Others, and Littlefinger. There are some really fucked up powerful people in Westeros, but no one is really a villain or a hero. The Others aren't really even evil, they're more like a persecuted and exiled people out for revenge. But they're definitely a threat, and they're the most mysterious threat in the story, so they're viewed as evil. And as "heroic" as Jon is, we don't know what he's going to turn into in Jon 2: Targaryen Boogaloo.

Maybe it won't matter and Dany won't go to Westeros at all. Maybe she'll burn her bridges and run off with Darrio on vacation to Pentos or somewhere nice to wait out the winter. Hell, maybe they can ride dragons into the sunset and drink Pentoshi martinis and do all the positions they can think of while everyone in Westeros dies.

I dunno. This series is unpredictable.