This is a pretty out-there idea but hear me out

As noted in the freshly updated metashield,

Heretics, Wizards, and Cultists are considered and known to crew as "Magic Users". The existence of magic users among crew is not shielded. Though knowledge of their abilities and goals is shielded. The shield prevents people from assuming magic users are inherently bad or antagonistic. The shield does not dictate the contraband status of magic user items. The shield prevents people from knowing the purpose and use of role specific items like heretic reality fractures/shifts or cultists pylons/altars. Though they may be suspicious of them.

It would be most appropriate to add additional magical roles (and possibly gamemodes, something like a higher chance of mundane magic with a heretic sprinkled in) to reflect the fact of magic users not necessarily being bad or antagonistic.

This addition will just make magical users not necessarily evil more plausible to players. Trying to act constantly that magic users aren't all bad feels HRP without some sort of reality mechanically reflected (MRP being players are encouraged to take things straight and as they are). Security not checking maintenance on green makes sense mechanically, so why not something for magic users?

I also just really want crew having latent magic to fight heretics with for counterplay. WIZARD BATTLE!

Despite not technically being an antagonist, it would probably be best if it was on the antagonist selection screen and rolled like an antagonist for the following reasons:

Mundane magical users should not be members of command at round start, so selection like an antagonist would be beneficial. Most mundane magic users will find themselves committing minor crimes, which is not befitting of command staff (see below about the vandalism).
Mundane magical users should not be another antagonist
Players will be able to opt-out or opt-in to being mundane magic users, with time requirements
Magical users would be given objectives that can be checked by the player (or overwritten, e.g. rev conversion)

Mundane magical users have two objectives:

Do your job
Awaken your power
Note that use of the power is not required.

On selection as a mundane magic user, powers are not automatically given. They must first be awakened by some event. It could be waiting enough time in the shift, falling prone enough, eating vermin, consuming a certaub sustenance, getting drunk, going to bed, sitting down for a period of time, reading enough books, praying at an altar, taking a specific type of damage, touching gold, being irradiated, being handcuffed, signing/stamping paperwork, or a whole number of other mundane things.

In order to determine what is needed to awaken the power with certainty, a contraband book is needed; It ought to be a guaranteed to spawn in the library on a shelf, a chance to spawn in the maintenance lockers, and in any hacked library vending machine.

This book when held alongside a drawing implement allows drawing a discernment rune (on inspect functionally identical to the heretic's transformation rune). Security should always treat these runes as vandalism, and punish fairly. One kind of ritual is permitted on this discernment rune, which is to discern the magical awakening requirement of the ritualist. The items needed to perform the ritual are random, can include common fluids like blood or welding fuel, but are never contraband.
This book should appear on inspect and sprite to be identical to the Mansus Grasp, but only when drawing the circle. The Mansus Grasp inspect text and sprite should be tweaked to be even more uncertain as to what it is.

Once the magical awakening occurs, the brain of the player forever has access to any random magical power (excluding wizard wands and heretic rituals) or any anomalous effect or any alien artifact effect. Being borged forfeits this magical power. There is no requirement to use the power for the objective; However, the player will have no knowledge of what the power does unless used. It could be produce potassium, an upgraded Mansus grasp... or smite.

To give librarians something to do and argue over, librarian SOP should be updated to disallow any security from permanently confiscating any books from the library, and instead must temporarily check them out if they wish to have them. This also gives a way for heretics to keep their book safe, if they can sneakily slide it into the library. Though, the heretic must trust the Librarian is robust enough to dunk on some thieving tider. This also makes Librarians taking stock of the library at the beginning of the shift as a way to deal with book inventory insertions. However, sliding the heretic book into a cargo order of books would be a way to get around this. To ensure book orders are untampered with, book orders from cargo should be locked behind Librarian access.

To serve NanoTrasen interests, chaplain SOP should be updated that they must verify, categorize, and regulate (pursuant to space law) anyone who is a magic user on the station. Chaplain stamped paperwork for experimentation to verify a magical power should provide legally immunity to the mundane magic user for one cast (in case they get something like smite). This permission cannot be given to the same crew member more than once in the same shift, though the Chaplain (and only the Chaplain) has no culpability if an already tested caster's brain is placed into a new body, to deceive the Chaplain into giving out another permission slip. Command members should never be human subjects of magical tests. Unadopted animals, such as non-crew monkeys, should be encouraged for use in testing magical powers that need a target.
Red Alert Chaplain SOP should permit the writing and reading of a Writ of Magical War, where any magical user who has been properly verified by the Chaplain may come the Chapel (or elsewhere, if the Chapel is unsafe) to hear in local chat the reading of a message calling to arms all NanoTrasen magic casters in defense of the station, permitting magical casting, including destructive or mess making effects, so long as it serves NanoTrasen interests. This message must be written during the Red Alert, read aloud without usage of radio, heard by the magic casters (God may allow some not present to hear the Chaplain's statement for this requirement), and loses effect instantly when the Red Alert (or other alert level) ends.

post scriptum

If there is blatant abuse of mundane magical users (by sec or antags), admins should be encouraged to spawn a (Grand) Wizard with the objective of rescuing mundane magic users (whom may choose to continue doing their job), somewhat like a magical ERT. Chaplain SOP should reflect the need to assist (Grand) Wizards to avoid NanoTrasen culpability for shitsec.

also shoutout to Komoni there should be a trait that makes oneself immune to being or being affected by magic, in return for a debilitating speech pattern called Stupidity.

Also make borgs unable to cast magic and immune to it like Chap, something something machine god in the sky protection