Those are all great points, thank you so much
At the Best of Texas Environmental Science session they emphasized that it is such a small program there is nowhere to hide. They said you will get to know the faculty, staff, and students very well and they said it is a tight knit community. The upperclassmen Enviro Sci students who were there seemed really sharp. The program staff said that 93% of grads were either working in the field or enrolled in grad school. My son is pretty introverted but he did say that the other enviro sci students there for the session were nice to him. He said that including himself, there were only about 9 students there for the session. Good luck in your decision making!
Most people are unfamiliar with their universities before they attend; that’s not such a big deal. As you take classes, you’ll meet more people and get to know professors and classmates alike. Professors are humans who generally want to help their students - that’s why they went into the profession, in part - so don’t worry so much about approaching them - it’s the same as approaching them at Texas A&M. There will also be teaching assistants in most of your large classes who will be more accessible and pretty easy to talk to.
Remember that even though UT is big, the vast majority of students won’t be interested in research experiences. Most students at big universities like that want to take the classes and get through.
At the same time, if you end up at Texas A&M it sounds like you have great academic support. And as others pointed out, you will be in the honors program there. A&M is so big that I’m sure you can find like-minded students there. TAMU does have kind of a reputation for being LGBT-unfriendly, though; I’d investigate a bit before making a decision on that one. There is a group on campus called GLBT Aggies.
For a left leaning queer girl,TAMU could be pretty unpleasant.
Have you come out to your parents? If not could they worry Austin will “make you” come out whereas Tamu would “straighten you out”, hence the idea that Austin is full of bad people who’d “lead you astray”?
If so, you’d have to have precise facts about academics, job opportunities, research opportunities, and perhaps speak about a faith group there is on campus that your parents would be familiar with.
You can’t get into bars until you’re 21, and if you’re admitted to 18+ musical events you won’t be served alcohol (your hadn will be stamped).
Can you promise your father that you’ll support the Aggies in every athletic game? Even against UT? 
UT is a better fit socially and it has a better program for your interests. From your posts it sounds clear that’s where you want to go…
Even if writing is a minor or secondary interest, UT-Austin, as well as the community, is hands-down the best place to be for writing strengths. Also, do not discount how important writing and expressing yourself can be for somebody in your position: as LGBT, activist, and – perhaps, as nobody else can have your subjective life experience – somebody who has not had the opportunity to be heard in the manner they’d want to be heard in life thus far.
Environmental science may be strong at both, though their emphasis may be a little different at each, respectively. For Marching Band, and other musical communities, I’d also lean towards UT. Many Texas institutions have rather strong marching-based activity (UNT-Denton has possibly the best percussion in the country), but I didn’t quite catch how it was exclusionary at TAMU. I wouldn’t be that surprised; I honestly don’t know anything about it. I kind of feel you’ll have to deal with dad the best you can; sometimes things don’t work out the way you’d hope, but it’s time for your life now.
DS is currently deciding between two schools and I am hoping he chooses the school that is the better social fit. College will be your new home for the next 4+ years so you need to be comfortable there.
@MYOS1634 I’ve been out for almost three years now and I think we’re finally at a place where I can speak freely and we don’t dance around it as much, so if that were the reason we’d have far more problems on our hands than just college. But rooting for the Aggies is actually a really good idea. I can swallow my pride for an afternoon.
@anhydrite That was very motivating, I’m super excited to have impending story deadlines, I might finally complete a readable draft at last. And first of all, UNT music is amaze and I’m going to Denton first chance I get to see my friend perform with them. To march at TAMU you have to join the corps. Not my cup of tea. Plus, it’s all about those gross UT uniforms that I absolutely love.
@lslmom good luck to your son. I agree. I want to be happy.
“I don’t know what sort of pact they made, but they’ve outdone themselves in creating high school part 2.”
This is my idea of hell, and I’m not a queer activist in Texas. UT sounds like it has no down sides except large freshman classes. You might be surprised: commit yourself to arriving early and sitting in the front row of every one of those classes, and you can make the most of the course. It doesn’t sound like you’re a person who will be scared to talk to the professor after class, and this way, they will already know your face.
Write out all the pros and cons and try to take this to your parents in a calm, rational manner. Spend as much time listening as you do talking. You may be able to persuade them.