I think that typing is a great long term strategy. To help your dd in the short term, you may need to take dictation.
DS now 13 had big problems with writing until he got to grade 5. We took dictation (trying hard not to put in the punctuation) if he was very tired. At other times, we had him dictate his homework on a small tape recorder. He played it back and then either hand-wrote or typed his work. This got around his working memory problems, but wouldn't help with weak muscle tone etc. These days, small digital recorders are fairly cheap.
He also used special software developed for people with dyslexia, including WordQ and Read and Write Gold. WordQ has a word prediction interface. The child types in a few letters and the software provides a list of words that start with the letters. The child picks the word from the list or adds letters to select it. This really speeds up typing.
DS used to play some Nintendo DS games that require typing such as Animal Crossing, and his typing skills improved considerably. This may work for your dd too.
