I would keep her in her crib for now...until she grows out of it. AND she still sleeps well in it. So that is a plus. When she is older or after 2, you can see then and switch her out.
Each child is different. For my son, from about 16 months, I put a little pillow in his crib for him... he likes it. I don't put a blanket though, he doesn't like blankets. But, he does have some stuffed animals in there with him...my son is the type that really likes stuffed animals, and it helps him to sleep. Yes, they will move around a lot during sleep. No worries. This is normal. We can't expect them to go to sleep and wake up in the exact same position. Even we adults move around in sleep. My son just made 20 months, and he does that too...but he loves his crib and it's his way of sleeping.
As long as your girl still sleeps well in her crib, and does not climb or jump out (which some kids try to do), then she is fine there. Remember, that switching to a toddler bed will be another transition to deal with... they are no longer "confined" in a "crib" and with a bed, they WILL get out of bed on their own and wander around sometimes or not want to sleep. Head's up.
We switched my girl to a "big girl" bed when we felt she was ready and more mature....it was about a little over 2 years old. By then she was ready. Each child is different. Luckily for us, she did pretty much stay in her bed and didn't try to sneak out. But it was a transition... it takes time. Be ready for that.
Good luck,
~Susan
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