1. Bows require you to VERY strong and specifically trained. Also, 'aiming' with bows is modern crap. With pull strength of about or more then 40 kgs (up to 80+), how long you will be able to actually 'aim' them?
You pull and release the bowstring in one motion. Of course, if you fire this way, it takes great practice to be able to actually hit anything...
Btw, a bit of historical info:
The Mongols (who conquered Muslim armies in Persia and much of the Middle East) were excellent mounted archers. About 1208 AD, they used high stirrups (attached to the horse's saddle for the rider's feet) which allowed them to shoot in every direction. They also used composite bows with draw weights of up to 160 pounds! They used metal thumb rings to release their bowstrings which allowed them to increase their range considerably.
Mid-eastern bows were superior to western ones. Range record documented was about 1000 yards (that's about 900 meters!). Of course, they didn't use heavy arrows or tried to actually AIM anything during those competitions, but it's pretty impressive nonetheless.
Of course, there are other, more primitive shortbows, but since I doubt that you have primitive setting... therefore, I think that you should pay attention to those facts.
2. So, if bows are so kickass, why crossbows pushed them out of business? Cause they are much easier to learn - you don't have to strong to wind them (you can use a crank, or a hook and a loop), you can take your time to aim, etc. Also, you can have many crossbows, have them reloaded behind the lines and passed in 'chain' forward. This really makes up for them being 'long-winded', heh. So, once they were in mass-production, any conscript could have used it with little degree of training. If quantity >> quality... it rules over quality.
So, in the light of above, my suggestions:
Bows should have 2 firing modes:
a. Fast shot. 2 Ap to shoot. (+1 AP if it's a powerful bow, like large composite or longbow) VERY low accuracy, but it increase with skill untill it's pretty decent. At uber levels you'll be able to select a perk that will allow you to make called shots this way, no additional AP required.
Moderate strength requirements.
b. Aimed shot. 4 ap to Shoot. (+1 AP for strong bows still apply) Decent (on par with xbow) accuracy, INSANE STR requirements - like base*2.
You should NOT be able to shoot more powerful bows this way, unless you are superhuman (or non-human altogether).
A perk like 'Fast aiming' can reduce it by -1 AP.
Also suggest a perk like "Fast reload" (require high Agility, means that you get an arrow out of your quiver as a free action), and “Strong Pull” - meaning your musculature and skeletal frame specialized for drawing bow, meaning that you use bow with +2 STR check. Can select a few levels of it, require certain skill in bows.
How fast one can shoot:
About 19 shots per second for bows in 'snapshot' mode (best result), for crossbows - 2 per minute if it's a model with a ratchet (but I doubt that you will include this one in the game, cause, while there were quite powerful 200-300 kgs pulll STR, up to 600 (maximum ever) but it will take several turns to wind them), and I guess 10 or so if it's one with a hook and loop.. but those are much weaker - less then two times more powerful then bows. (100-150 pull strength).
I'd say: Shot: 2 AP, reload - 6 AP. That's bare minimum. Anyway, how much AP for a punch? You should be able to land, at the very least, 3 punches while someone is cocking the xbow. So, if even it's 2 APs, is more then reasonable.
Fast reload and fast aim perks should apply to xbows too.
They should also have Str requirements, but MUCH lower (since you use your entire body to cock a crossbow, not just your arms). However, if you fit them only barely, you should get +1 AP to reload time, like in case of heavy bows (only there you get a penalty to shoot).
Also, about ranges.
It depends base range (very with power of individual bow or xbow) and on 'ammo', whether it's light arrow, or heavy AP arrow.
Bolts are heavy and AP by default.
Arrows: Hunting (light, not really damaging - well, basic), broadhead (most damage, less range), AP - least range, medium damage, AP (and very much so. With a good bow, you'll easily punch thru a decent breastplate from 100 meters... not to mention chain, leather or any other armor).
Anyway, overall suggestions:
Bows should be weapon of the elite: almost useless in the hands of weak and untrained, but with GREAT potential.
Crossbows are easy to use, but really slow and not that easy to manufacture.
P.S.
I know realism isn't the point, but real world differences between crossbows and bows can make for a good ingame distinction.
My point (in this post) exactly.