SasuNaru vs. NaruSasu

A brief explanation of these terms the way I understand them:
SasuNaru: Sasuke likes Naruto and seduces him; Sasuke will be the dominant one.
NaruSasu: Naruto likes Sasuke and seduces him; Naruto will be the dominant one.

And the (ridiculous) variations:
SasuNaruSasu: Sasuke likes Naruto, but hey, Naruto likes Sasuke too, so it's all good and my wild guess on who tops will be the one who has the name twice.
NaruSasuNaru: The other way around, no need to be redundant.

First of all: why is it so important for some people to make a distinction between SasuNaru and NaruSasu? I've read it before on fanfictions, "...this story is SasuNaru, but it could be NaruSasu too..." Really, why would you waste words on something like this? Is there an absolute need for you, the writer, to explain your story by these limiting labels?

Second: who cares who tops and who bottoms? Why do people insist on making same-sex couples have distinct roles? Why does one of the men have to be the "woman"? They could just switch from time to time, couldn't they, "variety being the spice of life and everything"...

Third, I'll humour you: who would be seme and would be uke, and still being in character?
If we look at the dynamics of the relationship between Naruto and Sasuke, we see that Naruto is desperately looking for Sasuke's acknowledgment and considers himself to be his equal. On the other hand, Sasuke is always trying to surpass Naruto and will not admit under any circumstances that he is his equal, for that would mean he failed in getting stronger.
So we have one boy who won't submit and another one that will only dominate. This, my friends, does not work. At least not in what I consider to be a healthy relationship. I never said that their relationship was healthy, though... But that's the subject for an entirely new post.

I'll wrap this up as it's getting far longer than what I'd expected. Anyway, I usually end up saying SasuNaru regardless of the situation because it sounds better, so there.