You've gotten a lot of good feedback, particularly about replicating the angle and snugness of the carseat (and the womb), but the one thing no one has mentioned yet is that your little girl is only 11 weeks old! She's still wee little, and in the world of sleep, she's still in the very early stages of development. Even Weissbluth, the king of cry-it-out, wouldn't want you to let her cry at this age, and not for at least another 6-8 weeks. The fact that you're getting her to sleep through the night at this age, by whatever means, is wonderful! You may never have to go that route.
As far as sleeping in the carseat goes, some pediatricians disagree, but there is no scientific evidence that there's a problem with letting her sleep in her carseat (or swing), except for the one already mentioned, which is a compromised airway. But you can address that issue with proper head support (they sell pillows for carseats that keep the head in an upright position). We had our son in his carseat in a co-sleeper for a while, and I felt just fine b/c he was right there with me, but we still had separate sleeping spaces. I might be a little more cautious with your daughter in another room, but really, it's just b/c we're moms and we're cautious, there's not been any reliable study done to show that you're actually taking unnecessary risks.
At 11 weeks, keeping her swaddled and cuddled, whether by your body, the carseat, the swing, or wedges (personally, I wouldn't use pillows and/or boppies, b/c of the risk of SIDS), is going to help almost any baby sleep, and clearly, with your daughter, this is the case. There's nothing wrong with that! You will get lots of dire predictions about how you're coddling her, how you're never going to get her into her crib, how you have to let her cry it out now, before the habits are formed. Just breathe, and follow your instincts. This is YOUR baby, you know her better than anyone, and she will develop and grow at her pace. You can, and should, guide her development (and there's plenty of time and opinions for that!), but that doesn't mean that she's going to follow any text book example of what "should be." For now, do what works, and re-visit the issue in a month or two. You'd be amazed at how much she changes each month for this first year. Nothing is set in stone in terms of her habits or her development. Seriously. You're doing great.
Hope that helps...