Enyoss not sure if you've done it or not but I'd love to see your mathammer on N17 to see how the new equipment and rules simulate (especially due to limited amount of game time i actually get to play due to real life and a limited gaming community.) Things such as gas, synth, toxin, close combat weapon interactions stat and skill benefits etc. I love seeing how the mechanics operate since I've forgotten most of what I learnt in school years ago... lol. Still love looking over this thread.
Long time since you posted but better late than never

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I haven't really delved into the N18 combat stats.
Mostly because, if I'm honest, the maths of it doesn't really interest me as much as NCE. N18 combat is much more linear: if you increase your attacks by 50%, say from A2 to A3, you increase the expectation and variance of your number of hits by 50%. There's no opposed rolls or dependence on enemy WS, it's just a set scaling (mostly - parry meddles with that slightly).
Also, NCE had a binary outcome for combat - one fighter hits the other, or vice versa (ignoring draws). In N18 both fighters can fluff all their attacks, or hit with all their attacks, and if you're attacking second you might not even be around long enough to attack at all etc.. This takes the whole concept of who 'wins' combat beyond simply who scores hits, but who wounds, fails armour saves, gets flesh wounds etc..
In contrast to the simple hit-scaling alluded to before, the enormous number of possible outcomes from all those steps means you now have to simulate entire combat scenarios rather than being able to solve the problem exactly as I've been doing up to now. Which is still pretty straightforward in many ways - I've already got a brute force combat simulator and have used it to see how much more effective a Thunder Hammer is over a Power Hammer for squashing 2W champions

- but not quite so elegant. And all the possible S/T/W/Armour/Weapon combos makes it hard to boil it down to nice rules of thumb.
One thing I probably will look into though is the effectiveness of weapon traits, e.g. all else held equal how does adding Shock or Power to a weapon change the distribution of the damage dealt.