Is it possible to do both speed reading & speech practice?
Yes, but not at the same time. I think it is great to practice both. Just let her know which time it is. If it is free reading time and she gets to read as fast as she wants, that's great. Then you can have a separate time when you have her read to you.
The first should encourage her to continue enjoy reading, and the second will help her form good sentences when speaking. With some of my boys, who needed help slowing down, it was good to have printed material that we could point to. The pyramid method also worked well, just to help them learn to read out loud. It also worked well with reluctant readers. It goes something like this.
Dog
The dog
The dog likes
The dog likes cake.
The black dog likes cake.
The black dog likes purple cake.
The black dog likes to eat purple cake.
The black dog likes to eat purple cake every day.
You keep the lines below the one they are reading covered, and keep sliding down the page with them. It helps the child notice which words were added and it helps them not skip any. It also helps reluctant readers as they only have to read one or two new words each time. In the end they've read a long sentence (which is usually silly and makes them laugh).
I need to give credit to the book Pyramid by Dolorez G Hiskes for this idea.