So for law enforcement we have a lot of muggle humans who have to deal with day to day crime in SD, which could be challenging when you could go from Mermen to Minotaurs with no warning.
Limp Lash is a level two spell that does damage to strength, dexterity and constitution each round until they hit one. It's a ranged touch attack with no saves on the damage, which makes it reliable, but you can just walk out of the effect so it isn't the best for combat.
For a trio of guardsmen trying to arrest a drunk half giant or break up a Minotaur domestic dispute its perfect though. It's cheap, broadly effective, and lasts until the lash is broken or you let go. Most people would probably stop resisting without needing to go to full paralysis, but normal guards should be capable of grappling a rapidly weakening opponent long enough to go there if needed.
Coupled with cheap stuff like Litany of Entanglement they would have a much easier time enforcing the law. For anything like riots or large fights Cloud of Seasickness would be a good way to dissuade people, and keep the most determined off balance until the lash puts them down for the count.
For the transit system,Mirror Transport is pretty ideal supposing that a constant item could get around the duration cost of passing through it.
When cast on a mirror, MT allows you to enter it (if it's large enough for you to pass through) and exit any mirror in 500 ft. It lasts hours per level, but each person to use it cuts an hour off that duration. If we can get around that with some sort of upkeep cost or something, then these could effectively be bus stations.
At that range they effectively cover a city block, and you only need one item to send people anywhere with a mirror inside of it. A station could consist of a single "outbound" mirror, and however many normal ones we need to meet traffic to that area.
Putting them everywhere would be silly, but in lines connecting districts of the city and in clusters around important areas they'd be workable and convenient. Most importantly, fixed range and restriction to carry weight only in items makes it a poor spell for any Tippyverse style collapse so we don't need any artificial restrictions to dodge that particular bullet.
Pellet Blast is the shotgun spell. It's level three, and hits a 30 ft cone with pellets dealing 1d8 per 2 CL (up to 5d8) piercing damage to everything in range. The tricks here are that it conjures the projectiles, has some limited variation based on material component, and hits everything in range instantly.
For random metals you get the regular effect, but silver, cold iron, and adamantine allow the conjured pellets to pierce the associated DR.
That's not a lot of damage, but it's very fuel efficient since a fixed amount of input materials will damage as many targets as are in range. It's also not limited to creatures, so it can shoot down projectiles if mounted on a moonchaser. It doesn't need much damage to knock stuff down, and it's easier to hit a target with a cone than a dart.
We could easily fill pocket spaces with scrap metal for barely any money and vastly improve our ability to shoot down ranged attacks without even getting into the special munitions.
It'd also be really fun for fortress defenses if firing bunkers were placed around the ground level near doors, and pointing down from the top of the wall at 15-30 ft intervals.
