Well you propose two standards, the first:"people that make the change but remain faithful to the gender binary." I think would exclude Brandon and Gwen as neither were on HRT, neither were under the care of a doctor, neither were preparing for SRS.
Second standard: "seek to live their live in their true gender". I'm not even sure how you would begin to qualify that.
Third, and this is the kicker, the real incremental method is to A) get these laws passed on a local level, B) get them passed on a state level, then, and only then, C) get a national law. There are two reasons for this. First, and the most important, employment discrimination cases tend to be filed on a local level first, then drift up to the state level. Such discrimination is hard - almost impossible - to prove, as most employers are not going to leave any sort of paper trail that would act as a 'smoking gun.' You would need some form of corporate communication stating "don't hire ->-bleeped-<-s" or something to that effect. Any employer, or their lawyers, will contend that the other person who was hired was "a better fit to our corporate culture" so some such nonsense, that though untrue, is again, almost impossible to prove. In a place like the SF Bay area where so many people apply for every job, many of whom are highly overqualified for them, its very hard for a person suing to meet the burden of proof that they were singled out for discrimination. Moving it up to a federal level not only makes that harder (as the burden of proof is even higher), its much, much, much more expensive. That's why most federal suits are done as class actions, the cost is too much for one person to carry, for as long as it would take - and the federal court system is very, very slow. Moreover, it would be much easier to get a fair hearing from the SF DA, or Jerry Brown on the state level, then anyone in the Bush Department of Justice.
One of the reasons that so few people in the Bay Area got all upset about EDNA is that we have those laws in place on a local and state level, and thus, have far less need for a Federal law - nor is anyone in SF under any sort of delusion that the Bushies in the DoJ would be jumping for joy to start suing their favorite major corporations on behalf of gays and lesbians, much less ->-bleeped-<-s. (And we have much bigger problems with Miss Nancy over the funding for the war and the non-impeachment stuff, then over the EDNA bill.)
The second reason for doing the local > state > national route is that by the time you get to a national level, you have had cases in lower courts that could be cited. By that time you have the beginnings of a body of decisions that could be used to guide to fashion the federal decisions.
And, perhaps there is no discrimination in SF (I doubt it) but in the 15 years that the local law has been in place, there has not been a successful lawsuit. As I said, its way hard to prove.
In the end, any standard on this that takes anything greater than presentation is going to be doomed. More MtFs have SRS then FtMs at the current time - do we exclude them? What about those who for medical reasons can not have either HRT or SRS? And, many, many, many of our brother and sisters can not afford it - they (like so many Americans of all stripes) are living paycheck to paycheck, often only a check or two from being homeless, the cost of the entire run Shrink > Endo > HRT > Surgeon > SRS is far beyond their means. Excluding the MtFs and the poor, and the sick, would make such legislation little more than a 'rich, healthy girls protection act."
We know through painful experience that freedom is never voluntarily given by the oppressor; it must be demanded by the oppressed. Frankly, I have yet to engage in a direct-action campaign that was "well timed" in the view of those who have not suffered unduly from the disease of segregation. For years now I have heard the word "Wait!" It rings in the ear of every Negro with piercing familiarity. This "Wait" has almost always meant 'Never." We must come to see, with one of our distinguished jurists, that "justice too long delayed is justice denied."