The size of their hands doesn't have as much to do with it as that the larger the coin the more visual the effect. Any of those routines that you mentioned can be done with quarters. However, smaller coins limit your distance from the audience and what they are able to see.
Also, Morgan silver dollars also have a really nice ring to them. Kennedy half dollars made before or around 1966 have some silver in them and ring rather well too. The sound just adds a little extra class to it.