Well, I think one needs to keep in mind there's "what one finds attractive" and "what one is comfortable expressing openly." I think you may have a point insofar as the gay community may be more conducive to individuals being more open about their preferences. I think it's really hard to draw any generalizations however.
Certainly I would like to account for the percentage of heterosexual males who are homophobic, and the degree to which they would NOT express a desire for more masculine females with candor. But in the absence of any data whatsoever, I don't want to assume anything. The end result is the same though, in that I agree it is too hard to draw generalizations (at least meaningful ones).
I think some of your difficulty is arising from too narrow a defined set of gender roles and sexual orientation. Even reducing female homosexuality down to "girls liking girls," one needn't define "girl" as "feminine." Butch girls are still very much girls. I'm sure at this point you're going to say you know this, but think about it for a moment. Are we talking about attraction to femininity or attraction to girls? That distinction is key, I think. There is certainly a lot of overlap, and both could apply to an individual, but then they aren't dependently linked.
Yes, but I would think that attraction to femininity should not be discounted even if it is an independent factor. For example, a girl such as yourself is homosexual from birth. But a large part of your understanding of what a girl is (or should be rather) is the result of what you are taught via societal norms. Even with insight and the realization that such things are artificial constructs (mostly), it can be hard to separate your current understanding of what a girl is from what was ingrained into you during youth right? So in that sense, I would think you would be attracted not only to girls, but also femininity, as that plays into your idea of what a girl should be. Anyway, what I'm trying to say is that attraction to femininity seems fairly part and parcel to me on a practical level. It's not a universal thing by any means, but it does count for something.
BTW, I say you not to specifically highlight you, just saying that - oh you know what I mean.
Some girls are attracted to masculinity, but prefer women to men. Some girls are attracted to masculine women because of the contrast, because they find the idea of a butch girl itself appealing for one reason or another. Either because the dissonance itself is appealing, or because there's still a remainder. This gets into very complex territory: ie. arousal over trying not and quite succeeding or scenarios like "being tricked into thinking it was a guy." There's also an attraction to the idea of a dominant woman, and masculine trails and roles are often associated with this. A girl might be attracted to girls but like domination. Similarly some people are attracted to the idea of an "emasculated" man, that is a male who yields in a stereotypically feminine way --- and I think those types of scenarios raise interesting questions of the role of power in sex. See Foucault.
Also one could argue butch girls are a "transition" for some girls who are dealing with issues of identity, having grown up thinking they were supposed to like guys and are perhaps still attracted to the idea of heterosexuality. In that instance a butch girl is closer in their mind to being with a male and subsequently more "acceptable." Maybe they're still in denial, or maybe it's just more familiar. Not sure how much of this I accept, but it's an interesting idea.
Some girls are attracted to BOTH women and men. Some people will tell you that they're attracted to an individual and that trying to define that attraction in categories is doing it violence.
Given the above, yes I would say that generalizations in attraction would be most difficult to pin down. But it frankly didn't occur to me (way back when asking) that the differences would be so varied to the degree that they are.
Here's a somewhat related question. If a homosexual girl likes girls that just happen to resemble herself, then would that girl be physically attracted to herself? I know that must sound like an odd question. But as it is technically possible, I wonder if it ever happens in real life. This is a phenomenon that - for obvious reasons - could not exist in heterosexuals (outside of MeHarmony).