in your profile, you should list where you are from, so we will know what kinda weather you get, helps if you have any questions... besides everyone will keep asking.
so, where do you live ??? I can tell it is further north of me cause my japanese maples have be torched by the sun, but they do look really nice in the fall and spring! I really should get rid of them, I just haven't the heart as of yet.
Now, I am not as expert an anyways, when it comes to japanese maples... but In my opinion, I would probally just let them grow for now... and allow the trunks to really thicken up, besides they can always be cut later. If one wanted to you might wire the trunks, to get a little more movement in them??? Since you have 50 to 60, you are going to need alot of wire!!!
Perhaps sell or trade some for other plants... there is a selling forum at this site, you might put a listing there.
Good Luck