With your daughter being a year old, I don't think sleeping in her car seat is preferable. My son has always had a sensitive gag reflex (as does his father, and his father's mother, so he comes by it honestly), and he throws up easily when he gets worked up crying. So I can relate. I just wanted to let you know that your daughter is not alone on the vomiting thing, and I don't necessarily think it's reflux. At least it's not with my son. It's just if he's crying hard, he'll start coughing, and then the vomit is next. We have worked on not getting to that state, but if he's really upset/crying, we can pretty much see the vomiting coming. That goes for a good coughing spell too. He'll vomit sometimes after a really hard coughing spell. Sensitive gag reflex.
As for the sleep issue, personally, I'd be ok with the rocking/bottle to go to sleep routine. If that's working, why not just go with it? And have you tried putting a bottle or sippee in the crib with her so if she wakes up, she can get it on her own? This worked for my son. I know we're not supposed to let them have milk at night, but if you are giving it to her anyhow, and you're not getting her up to brush her teeth, what's the difference if you get up to give her the milk or if she has easy access to it herself? Or you could use water, or maybe that's what you're already doing. Either way, I'd try putting her bottle or sippee in the corner of her crib, if you haven't tried that. Then, if she wakes, you could go in, show her where it is, and maybe eventually, she'll realize on her own that it's there.