You are trying to help the people who are supposed to be cannon fodder?
Against magic, yeah.
Nightwatchmen are the canaries, their dying is supposed
to be the early warning system of a facility. And, gangers, unless you are dealing with top tier gangs, should be dying to magic easy.
The nightwatchmen have two jobs: 1) Observe and report and 2) Die or be knocked out(preferably be knocked out). Gangers aren't going to mess with a group of Shadowrunners who are clearly better prepared then them, unless they are in a large group. And even then, Gangers are, unless they have a mage, supposed to be scared of magic.
If your runners are good, the nightwatchmen or gangers have no clue who they're up against. And this approach seems to end in a road where the only NPCs we can do anything interesting with are rival Runners - even immediately post-chargen, or possibly peons lucky enough to have Counterspelling support. That's extremely boring to me.
I also think it's boring that mundane guards and NPCs have absolutely no chance against charms or illusions or having their face melted 3 dice (3 WIL) vs. 11 - 15 (5 MAG+6 Spelling+2-4 Focus)? What's the point? I find it boring that the go to solution is, get the Mage there. I'm not trying to nerf Magic completely, I'm trying to give NPCs a fighting chance against it. 9 dice (3 WIL+6 ESS) on average, against 11 - 15 is at least kind of a fighting chance. Not much different then the disparity often faced in gun-battles, anyway.
To be more cyberpunk I will go the way the more you have cyber the more difficult it's to use magic against you.
I will probably go the threshold way (in the same way as resistance object) according to the essence loss. Something like :
0>1 : 0 threshold
1>3 : 1
3>5 : 2
>5 : 3
BA
Interesting. It does absolutely nothing for unaugmented mundanes (which is actually my goal, making the setting more cyberpunk was just a poorly thought out rouse of a premise), but that's an even greater boon than extra dice. 6 dice = 2 hits on average, outright Threshold increases would be quicker though... hmmm.