So, leaving weapons and complicated spreadsheets aside for a minute.
I'm basically thinking that NPCs/monsters (I'll call both NPCs in this post for simplicity) will come in five mechanical types. These are civilians, grunts, veterans, antagonists and hordes.
Because Monitors isn't a combat game as such, there's a reasonable chance they'll end up confronting civilians. There's petty criminals, scientists, bystanders driven insane by alien influences, hivemind drones, factory bots, and all that sort of thing. There's also a lot of potential for civilians to be involved on the Monitors' side, perhaps if their spacecraft is attacked by pirates, or if they're rescuing captives. Civilians will have a single Wound, and any successful attack that penetrates their defences will take them out of action for the rest of the combat. They will have minimal combat skills, and will typically have only one or two professional skills worth mentioning, though these may be very high. Typically they will avoid combat.
This might seem to be undervaluing non-combat NPCs, but if you think about it, the non-lethal combat system of Monitors should make this completely appropriate. There's no need to layer on unconvincing survivability to NPCs just to let them function (a bugbear of mine relating D&D 3e NPC classes) because they're not going to get killed off, so you only need to worry about them getting captured or leaving them behind. The main exception will be if you're trying to protect them while they do something important, like carry out repairs.
Grunts represent any NPCs with some level of combat experience. These are things like hired thugs, security guards (and bots), ordinary soldiers, pirates and so on. Their precise value will depend on their combat skills, which aren't fixed, but will tend to be between 4-8 in most cases. Grunts have a single Wound, which means they can be taken out with one good attack; this is vital for sentries and the like. They appear in only small numbers, because once you have more than a handful, you should be using a Horde for mechanical balance.
Unlike civilians, Grunts are affected normally by soft weapons, inflicting a Blind or Slow die rather than taking them out of action.
Veterans are competent, well-trained soldiers. They aren't necessarily more skilled in combat than Grunts, but are more durable. In general, a group of Veterans should be a challenge for a similar number of Monitors. Veterans will have a similar number of Wounds to Monitors (I'm currently thinking both will have three to five). Veterans represent things like bodyguards, elite strike teams, assassins, and anyone else who gets their own theme tune.
Antagonists represent major threats of some kind. They are likely to have good equipment, good skills (not necessarily in combat) and plot armour represented by multiple Wounds. It doesn't really matter whether they're a mad scientist, a pirate queen, a huge monster or a malfunctioning warbot, they still want to absorb a few hits to be a satisfying opponent - though those without combat skills won't be able to fight back directly. Some antagonists will be a significant threat in combat in and of themselves, while others are threatening because they command lots of minions, control dangerous machinery and so on.
Hordes, as discussed previously, represent large groups of enemies that are generally relatively weak. They are hard to fight effectively without weapons designed for that purpose. I'm currently thinking of replacing the earlier rules with a Wound-based system, where Hordes will have a significant number of Wounds (5+) and this will modify both their and the Monitors' effectiveness.