I agree with the basic theme of the other moms...she needs more happy, quality time with you, and it sounds like most of your time is trying to get her to do the things she needs to do so that most of your time is negative. I fell into that trap with my boys and it really is quite easy and quick to get out of.
One more thing you can try is to check out www.housefairy.org. This practically eliminates you from having to be the "bad/mean mom". Maybe you could sit down with her and ask her if she'd like to play a game with you... I find that when I give my boys (5&7) 15 minutes right when we get home, they are happy and leave me alone to get dinner done...otherwise, they're in my face with everthing like "he hit me!", etc. Another thing is to trade off every 15 minutes...she gets to do something she likes for 15 min WITH YOU, then she does 15 min of chores, 15 minutes of playing alone, you get the idea...
Bottom line is, we all need to know and feel we are loved and wanted and a lot of that is shown by actions and words. Kids understand a lot more than we think they do, and even if they don't, they'll appreciate and understand the time and effort you put into trying to get them to understand why you yelled, why you were mad, why they need to do things they don't like to do, etc.
Also, try to use examples of positive vs negative outlooks on things. Think of it as "The Secret" for kids. Is it really the end of the world and you're the meanest person on earth that you won't let her wear a tank top when it's 30 - 40 degrees out? Ask her what she thinks about it...what are the consequences, etc. Is there another way to look at the situation?
(To be honest, I'm still dealing with this issue with my 5yo...and I finally told him that when he wakes up whining and complaining, it puts everyone else in a bad mood and makes people not like him or want to be around him, but when he starts the day with a smile, everyone has a great day. I can honestly say that we now have more happy days though there are still some days when nothing will make him happy and I tell him it's his choice to be happy, mad, or sad, and there are consequences/effects for each. When I give him the choice to be happy or mad with "effects" of each, he always chooses the happy path...the mad little boy disappears in a matter of seconds.)
I think I rambled on this enough...sorry about that... :)
Good luck...and the first thing you do when you see her is smile and give her a hug...that's always a good start... :)