The government would also point out that in the event of the Kingdom being attacked by outside forces yet again, all species are expected to come to the realm's defence on the basis of "better the devil you know". Those who wish to steal the Kingdom's magical powers will take them from everybody.
The Queen and her Council will be notified a month in advance of any gatherings where there will be fireworks. There have been too many previous instances where firework displays have been used as a cover to hide some nastier spells being unleashed against the innocent. Those organizing such gatherings will be vetted so if any witch or wizard thinks they can disguise themselves to get around this, think again as the Queen and her Council will put all the detect/reveal charms they have on any candidates and there are hundreds of such spells.
The Queen and her Council expect high standards for magically produced fireworks. The Queen especially likes artistry and magic can be used to produce something special here. Any wizard with useful hints and tips here who is willing to share said hints and tips will be rewarded by the Queen.