First off, don't worry about choices like having to put your daughter in daycare full time. We all have to make choices and sacrifices that may not be our ideal choice. You are doing what is best for your family right now!
And, if it makes you feel any better, we all feel like we are failing as parents and screwing up our kids whether we stay home or not. You were chosen to be your special little girl's mommy and YOU are the best for her. You are not screwing her up.
All that being said, my first thought is, you want to stop in at the day care here and there to do random checks and balances unexpectedly. Maybe during lunch hour, leave a bit early one day here and there, etc. This gives you the opportunity to see how the daycare functions and if their tactics and philosophies match yours. They can tell you all day long what they do, but this gives you the opportunity to see first hand how they work. This is your best option for making sure she gets a similar influence at home as well as daycare.
Secondly, always keep checking around at other options, daycares, day schools, etc. You never know if something comes up that may be a better match for you child. You mentioned that she is very vocal, well some schools work best with a loud bunch or some work on teaching kids to use an "indoor voice".
I work out of my house now, but in the early years with my first son, I needed daycare and I was lucky enough to work out a alternate schedule with my job. They let me come in at 5 am and get off at 1. So my husband dropped off at 8 when he went to work and I picked up by 1:30, then his exposure to the daycare was more evened out with my exposure to him. Not sure if this is an option for you but it is something to think about.
Last but not least, I had a very hard time finding a match for my son with daycare. Part of it was a new mom thing and the other part was my son was overly sensitive. That being said, the final daycare we found to be the best was a church-based daycare. They had so much focus on the love and appreciation aspect of life that he was able to grow and enjoy his time as well as learn to be a loving, mild-mannered little boy.
Good luck to you, I know how hard it is. Kids do that to you.