I guess it depends on a lot of things. 1. If you have early breakfast. 2. Which character you have for disembarkation.
We just sailed on the Wonder in February. We had a late breakfast at 8:30 and were probably off the ship by 9:30/9:45. We had Mickey. They disembark the ship by character.
I'm not sure what time they started disembarkation. But I know we did not dock until 6:30 a.m.
So I guess to answer - if you had a late breakfast, 10 a.m. might be a perfect pickup time since you will also need to get your bags and clear customs in Miami. But if you have an early breakfast, you might want to get an earlier pickup.