welcome to the community :)
Good call on the need for archers – from my experience having solid shooting is crucial. It allows you to get rid of key targets (necromancers, crossbows, standard bearers) fast and helps to soften up the enemy as he approaches your line. My standard setup is:
4 specialized archers (middle of the 2nd line)
2 “flankers” crossbow/melee hybrids (on both sides of second line)
Archers are focused on maximum damage at range and double as polearm users when tactically preferable (read: when they’ve already killed everyone who’s not in melee with the 1st line). They use bows (backup quiver or 2 in your bags in absolutely mandatory) and 2h-reach weapons: pike at first as they need boost to melee accuracy, then switch to longaxe (best unarmored HP damage, shield breaking). If I know I’m facing heavily armored opponents in next battle (say, orc warriors) I change their equipment to crossbows and billhooks. They wear closed mail coif (or any named helmet that doesn’t limit vision… you can get away with a -1 vision if you roll Eagle Eye trait) and Mail Shirt-grade armor (130-150 armor). In the endgame it’s prudent to give them Steel Brow and better chest armor to avoid embarrasing 1-shots from crossbows.
Do note that after some recent changes it’s quite safe to shoot directly from behind your brother’s back at someone who is fighting him in melee, so it’s theoretically possible to go full-on range combat and forego melee completely. I just don’t think it’s worth it as polearms offer great support and flexibility (especially when fighting skeletons. On the topic of skeletons remember that unlike dem bones their armor is not resistant to ranged attacks).
Stat-wise I focus on ranged skill (obvious), fatigue (you get a silly amount of shots with Berserk and need endurance to support that) and ranged defense (never let them stay in melee), in that order. Initiative (for faster movement and possibly Dodge bonus) and melee skill (for actually hitting something with a polearm) are nice secondary stats when you’re hit with bad rolls on the main ones (in general never pick up a roll of 1, and pick a “secondary” roll of 3 over a “primary” of 2).
In order to make them effective you need them to come from a decent background (poacher/hunter are a good start, sellsword is optimal) and have as least 2 stars in ranged skill (you want them to hit at least 80 in that).
Perk-wise it’s all about pumping out the hurt, and in a hurry. My absolute mainstays are:
1. Bow Mastery – essential for out-sniping goblins and other rangers
2. Berserk – you’ll be getting a lot of kills later on as with decent skill you can easily pick the softest targets
3. Killing Frenzy – great synergy with above for a snowball effect
4. Crippling Strikes – for softening up scary targets (*cough* orc warriors *cough*) that you can’t reliably kill before they reach your line. The injuries are rather random and range from “mildly annoying” to “absolutely crippling” but either way they stack and add up quickly
5. Fearsome – absolutely amazing when facing tightly-packed living targets (sadly useless against undead) – their whole formation can scatter before they even close the distance between your lines
6. Fast Adaptation – for dueling with other archers and gaining something even from missed attacks
7. Quick Hands – mandatory for using a 2-hander effectively as otherwise you waste a whole turn while switching weapons
8. Footwork – with focus on ranged combat/defense and light armor you are dead meat in melee, if anyone puts you there (that damned orc warriors again) you need to get out ASAP
The rest is not as crucial and more debatable IMO, here’s my opinion:
1. Bullseye – used to be OP and pretty much mandatory, now it’s not really crucial – the bonus is rather small and with smart targeting/waiting not needed all that often
2. Steel Brow – a potential life-saver, but with a good build and defenvise perks (see below) headshots are very unlikely to occur at all. You gotta ask yourself one question: do I feel lucky?
3. Anticipation/Dodge – mostly taken so you can avoid getting sniped on turn 1, their usefulness depends on how fast you can take out the opposing rangers, and what are your stats. If you have at least 20-30 base (as in, not factoring any equipment in) ranged defense and a decent amount of both HP and armor Anticipation is sexier; if your ranged def is lacking but you’ve got around a 100 initiative at the start of each battle Dodge will serve you better. Never take both at once, you need those perk points elsewhere
4. Crossbow Mastery – crossbows are really good regardless of the perk, and it doesn’t add anything special (unlike the bow mastery). Take it if you’re going for the “war” endgame crisis or plan to hunt tin cans on a regular basis
5. Head Hunter – can get you a spectacular 1-shot-kill but also hinder you when the previously undamaged helmet stops a shot that would otherwise kill an armorless enemy. I skip it on my latest builds
6. Pathfinder – potentially useful for getting to an advantageous position, loses value if you mostly stay put – a matter of your preferred tactic. I skip it
7. Bags and Belts – currently rather weak, at any rate not much needed – at the beginning 20 arrows will last you entire fight, later on when you run out you can just switch to a polearm (you kill important targets hanging out in the back first). Skip it hard.
8. Executioner – nice synergy with Crippling Strikes is undeniable but 20% is just not worth a perk point when competing options are so much better. Viable if you wanna go full “glass cannon” mode
9. Axe Mastery – a potentially nice addition if you use a poleaxe often, but your melee-oriented bros have ways of dealing with shields, so just stick to what you do best – turning enemies into pincushions. Skip.
10. Polearm Mastery – come hell and high water, I’ll still skip it hard. Hell, I skip it on dedicated polearm users, that’s how useless that perk is.
I’ll come back later to elaborate on “flankers” and ranged combat tactics. Hope the above helps you already.