I would go back to rear-facing, absolutely! REAR-FACING CHILDREN ARE FIVE TIMES SAFER than those riding forward-facing. Consider yourself lucky if she's is still willing to face backwards. When mine was that age, it was becoming a huge struggle to get him in the seat, because he REALLY wanted to face forwards. (Before I could get him clipped in, he'd squirm around and face forward in the rear-facing seat, like he was riding in a chariot.)
There are now car seats on the market that can be used in the rear-facing position for up to 35 and even 40 pounds. (Sunshine Kids Radian80 and XLT go to 40 pounds, Compass True Fit and some Britax models go up to 35 pounds.)
It doesn't matter if their feet have to go up the seat or they fold them - in the event of a serious car crash, it could mean the difference between a broken leg and a spinal cord injury.
That might be uncomfortable for an adult, but not for children.
For more on the advantages of extended rear-facing (for as long as possible), and then, once forward-facing, using a 5-point harness booster seat for as long as possible, see:
http://www.kyledavidmiller.org/car-seat-safety-rear-facin...
http://www.cpsafety.com/articles/StayRearFacing.aspx
http://www.car-safety.org/rearface.html
http://www.cpsafety.com/PDFfiles/RearFacingBrochure.pdf
My six-year-old will be in a 5-point harness until he's 80 pounds.