Regarding the ammo, doesn't the very small size basically make them unable to harm armoured targets, or does the power of the (cross)bows make up for that? Or does the coverage of armour make up for this by sometimes allowing projectiles to bypass armour (like hitting through gaps in the armour)?
It's a bit of both. Regular bows and crossbows will not be able to do much against serious armor, but longbows and arbalests, especially with piercing ammo, perform pretty good. On the other hand, serious armor is expensive to make (and a full set is very rarely generated on invaders) - and cheaper, lower tier armors have gaps. Simultaneously, my mod still has heavy and powerful ranged options, such as atlatls (javelin throwers) and hand ballistas. Slings also perform well against armor, although they are more luck based than other ranged weapons.
I heard halving velocity modifier of unarmed attacks already solves a lot of issues, do you recommend this with your mod too?
This is what Revised does, yeah. Revised also removes biting and scratching from civilized creatures, because of how ridiculous those are within the game's mechanics. Both of these fixes work well with my mod.
This seems a lot in line with battles often not having too many casualties until a rout broke out.
Yep, one of the mod's main goals is to tone down the quick and random lethality of the vanilla DF combat and make the choice of armor less streamlined. Also, I feel like this has a positive effect on the storytelling aspect of the game, as there is now more room for mistakes in combat: having multiple viable armor choices gives the troops more character, and many militias who would have inevitably died in vanilla may end up wounded, yet saved by their comrades.
I take it you lowered the weight of your armours by lowering the size, doesn't this also make the armours weaker and easier to broke by repeated hits?
Short answer: no, lowering the layer size doesn't make the armor any weaker.
Long answer: due to how DF combat formulae handles armor thickness, there is no settling point of difference between the layer size values of 1 and 20 (20 being vanilla for plate), unless the armor in question is sized for a creature with a body size value of seven figures. Essentially, the layer size will only start to matter when worn by something the size of an ogre - and the armor sized for such a creature will be so thick that the difference in protection becomes irrelevant. Also, the weight will render the wearer immobile anyway.
So I wonder, how often do armours break in combat, and how much of a problem does exhaustion become in prolonged big fights?
There are too many variables for any combat situation to give a definitive answer here. In short, plate armors break less often than they do in vanilla, and exhaustion is much less of a problem even for the heaviest armor choices. Both still occur, but, in general, armor in my mod is more durable (due to weakened weapons) and less of a liability.
It should also be noted that exhaustion depends on many, many different factors and still plays one of the most decisive roles in combat - and will continue to do so until Toady teaches the AI to preserve stamina.
Also to calculate weapon sizes and contact areas in attack do you use specific formulas, or do you kinda improvise per weapon so it feels right?
Generally speaking, I use real life weapon examples, with the help of modern replica shops and extensive googling.
For the weapon sizes, I've calculated that for an iron weapon to weight somewhere close to 1 kg in the game, the size must be about 150. I set all sizes based on this ratio and the real life weight of the prototype weapon.
For the basic edged attacks, I use the prototype's edge length and, in case of axes, axe head lenght, converting them from inches to raw-units by a ratio. This ratio is based on a number that I've found (after some testing) to be a quite reasonable penetration depth for the short sword (2000), equated to a reasonable blade lenght for the short sword (20 inches). Thus, I multiply a real life value in inches by 100 to get a game-friendly value. It turned out to work surprisingly well in practice.
Things start to get a bit more complicated when it comes to stabbing and other special edged attacks, although the same ratio is used for the most part. As a general guideline, stabbing contact areas equal the prototype's blade width divided by 10; thrusting equals blade width; clean slashes have blade length multiplied by 10 and have limited penetration; cuts are equal or half of blade length and their penetration equals blade width. And then, some attacks have it more arbitrary.
For blunt and pseudo-blunt (fluke/spike strikes) attacks I mostly use arbitrary numbers that are given with the game mechanics in mind. Penetration depth of fluke/spike strikes is capped by the prototype's fluke length, although it is occasionally made lower, for balancing reasons.
The way I calculate velocities is all over the place, but the most important numbers here are the prototype's total length in inches and the total weight in kg. If you give me these two numbers and describe the weapon, I can calculate the velocities for you. Or you can just use the velocities from the closest analogue in my mod.
For attack prepare and recover times it's best to simply use analogues, as those are even more all over the place than the velocities.
I also used to have some genius formulae which I've used to calculate the proper shoot forces for ranged weapons, but I've lost it. So, again, analogues all the way.
As for armor, I got to say that DF item modding lacks the possibility to properly implement lamellar armor and the like, as the armor is either rigid (like plate) or elastic (like mail) - there is no achievable middle ground. My mod does it in a half-assed way: lamellar armor
can deflect blunt force (so, essentially, it's rigid), but has a relatively high chance (33%) to let
any attack path through; on the other hand, it is relatively light, while covering many bodyparts. I've yet to come up with any way to implement it better.
Layer sizes for my armor are generally made with weight in mind, but you can safely use them by analogy (10 for plate, 6 for mail and so on), as thickness doesn't really affect combat performance anyway. One way to simulate functional thickness, though, is to have the same armor pieces layered upon each other, so keep it in mind for layer permits and the [SHAPED] tag placement.
And yes, you do have my permission, as it is stated in the main post. Regarding making new items in the groove of the mod, I might also be able to give more precise answers to more precise questions =)