I really like Smith Somersault Squats like the ones in the Joe Daniel's video. They don't aggravate my knees or back at all.
I don't us as high of a block to lift my heels. He has 2 or 3 inches there. Just a plate is enough for me, but I'm also a lot smaller than and likely more flexible than he is. And I don't have someone help me hold the bar as he shows. Holding it yourself limits how much your can use your hands out front for balance, but I haven't found that to be a problem.
Strength is the biggest limiting factor for me. He's doing them with 35's on each side of the Smith bar. I only use the bar, and still have a hard time getting above 8 reps before failure, then dropping sets down to 6, 5 reps. especially if I do them at the end of a leg workout. I'm not strong enough to use them as a high volume finisher, even with just the Smith bar. So if you are thinking of doing high volume sets they may not work for a lot of women in that way, but you may be a lot stronger than I am. They do REALLY hit your lateralis (quad sweep) if you keep your stance close like that.
Here's an older thread I had on trying to develop more sweep without bulking up my teardrop area. This is how I first heard about them. There are some other tips and videos there you might find useful as well.
Best to you!