Hello, ma'am. I just wanted to say thank you for your writing.
My work affords me time to mull over ideas. I wanted to share some with you, because they wouldn't fit right now with the current narrative. Hopefully you can work some of these ideas into your plans.
One idea is that of an Empty Gun or Blank Gun. It has no preset transformation. Instead, you can put in magical compensates like a dry potion (think Crystal Light drink mix or Alka-Seltzer medicine, mix with water - instant potion), or an herbal infusion (basically, a tea bag or a Mr. Coffee brewer - water forced through a filter containing magic ingredients.) into an Empty Gun and if what you did has magic in it, it will treat what you loaded as ammunition. For one shot, then you need to reload with the same or perhaps another mix. While anyone with magical training can make their own mixes (just like some people pack/press their own bullets) I can see MTI selling pre-made, well-tested magical mixes for use with the Empty Gun. Perhaps leading to a chain of magic supply stores selling recipes, ingredients and tools.
I also thought of MTI selling herbal compounds (Magical components mixed into a cream base - can range in consistency from whipped cream to cold compress cream per recipe. Stable, good for medicine and make-up.), or incenses (a treatment of magical materials, made to be invoked when burned. Lasts as long as the fuse/wick burns, so good for magic that needs a duration.)
I was thinking that the girls (and Jon, though maybe Jon(June?) should be included among the girls. Is it possible for Jon to wish for a Magnum Restoration Gun that works for 1,000 days after the fact? I can see him experiencing being a girl so to be a better guy in the future.) I digress, I was thinking that the girls could be a new coven of witches under the tutelage of Jon's Mom Linda (Jon's Mom hasn't mentioned magic to her children - maybe there's a reason for that. Maybe one needs to be a certain age to learn magic according to the local magic authority and Lina though she would instruct Jon and Zoe together, or maybe Jon's Mother had a bad experience with magic and walked away from the practice. I can't be easy to be the child of a witch/magus - if you can see fae/goblins/spirits/daemons/outsiders, they can see you. And steal your homework... or your boyfriend - that spirit lived off of the despair of others, and was good at what it did. Maybe too good.) Zelda's Mom, and Jon's Grandmother (I like to call her Esmé, to give her an Old-World, emigrated to America feel.) Grandma's grimoire would be a valuable shared resource.
I can see the girls playing with magic, within set bounds - and being expected to clean up their messes. (The best way to learn!)
I can see the Moms (Team Mom?) giving tests that the girls need to clear to advance - not unlike getting stripes on your belt to advance in rank in martial arts.
I can also see the girls 'deputized' to help with magic rule enforcement. They fight minor fae, elementals and spirits (Like trickster spirits - Fox, Hare, Rat & Cat (best frenemies!) Raven, and hir siblings, Magpie & Blue Jay (the terrible twins!), Grandmother Spider, and introducing: Coywolf, smart as Coyote, but bigger, stronger and very streetwise. (Coywolves thrive in cities.) Guest starring: Unicorn/White Hind) that would be a waste of time for the adult enforcers, so the adults can spend more time on cases that involve public safety. Like the fact that the local gang-mob (as in they are a little like a gang and a little like a mob. Call them a gang with ambition and competence.) seems to have a diabolist in their ranks, and is passing out demonic gifts and is rustling up imp/lemure helpers to bolster their ranks. Or that there may be a vampire infestation in town. (It's always hard to tell, masquerade/hiding in plain sight is the law among vampires...though with recent events, maybe recent newborns and pragmatic elders disagree with that law? I can see Gen-Y/Z Vamps wanting to go public and ask permission before drinking blood, or just paying donors for blood, or try to live off of animal blood - imagine the convenience of walking into a kosher butcher and being able to buy cow's blood normally used in Passover by the gallon for food. No more bitting rats/pidgeons and getting small sips of toxic (literally, rat-poisoned) blood).
The chaos of magic being revealed to the world would be on-going. Perhaps the veils that hid the supernatural are starting to fail. Nothing magical about it, cameras/cell phones are everywhere, and connected to everywhere with the internet. Perhaps the Navy has been in contact with the Merfolk for decades? Now they come out to humanity, because there is no point in hiding. Or perhaps a dragon is tired of hording gold and wants to horde sports memorabilia for a change of pace? Perhaps this was the point of giving Jon the stone- to tear down the veils between worlds. To what end? Maybe the veils were already failing, and this prevented a war between humanity and the supernatural? (as in a war to destroy our technology to keep the veil more or less intact.) Or maybe there is a common Entity, something Outside - dead but dreaming, that all the folk of the Earth need to unify against?
I also have ideas for a 'meta' attachment - it fits on like a silencer to any Transformation Gun and can attenuate the transformation by percentage. Also, focusing prisms/lasing chambers. One can combine multiple shots into one with this. Stun Gun - A self defense gun that knocks a person out briefly. Anesthesia Gun - Self Defense Gun. Numbs whatever limb/part of the body it hits. Victim feels no pain or sensation, has no strength and limited coordination in targeted area. Like dipping your entire arm in nonvaccine.)
With that, I thank you for your time. It's past time for me to retire. Sorry it's all a jumbled mess, I was typing this steam of thought...but my streams of thought are more like clouds.
Thank you again.