Some points I wish to make.
1) There is such a thing as objective beauty, which is different than subjective beauty. Just because a character is found sexy by some, that does not make him objectively attractive by human standards. It's not like someone like Solas, with his "creepy-drug-dealer-in-a-van" look, would be the kind of person that makes people turn their head to admire his beauty. And as I mentioned before, just because the Penguin from the Batman comics has many fangirls, that does not mean he is an attractive character. In the case of characters like Solas, I personally believe what makes him attractive is more the knowledge that he is a romance option rather than his actual looks. Fangirls swoon over Solas because he's a romance option; if those same ladies were to meet a guy like Solas on the street they most likely wouldn't as much as glance at him once.
2) Physical attractiveness is extremely important. This is a videogame; no matter how awesome the plot will be, the characters of a videogame need to be heavily defined by their appearance.
I am still of the idea that the female companions look much more akin to the canonical idea of beauty than the males do, and it makes me feel like, once more, female players get the short end of the stick while the greatest care is put in making the female npc appealing.
You point out Solas as a comparison, when Cullen and Dorian both fit into your "Objective Attractiveness" On top of that, Varic is easily a dwarf that would turn heads given he is far and above more sexy looking than any other dwarf. Combine that with the 4 other male companions who will easily have followings for other reasons and it gives girls quite a bit more choice.
As for the females, Vivienne is the only one i would say is "objectivity beautify", but i personally don't find her attractive. Cassandra has become very haggard, gaunt, and worn down from fighting a losing battle for years, and her appearance, while not unattractive, would not turn many heads. As for Sera, while she is pretty, she is not overly striking for an elf, just average. And i haven't seen enough of scribbles to say much on that matter.
Point is, this game is entirley subjective, as it;s all about your, the players, opinions. But even if you wanted to take that away and make it an entirely empirical survey, the girls still don't have some crazy edge over the men.