Great job on the Unicorn Frieke. As for a fast drying finsh, as the kids are older and are not likely to be trying to eat the unicorn hehe you could put a laquer such as Deft on it. The spray Deft drys very quickly if not put on in thick coats, use 3 or so thin coats. Stand alone puzzles are fun to make and seem to sell pretty well at the craft shows.
DW