Hey Hutch awesome post!
I reckon if we could organise some matches and test this out it would be awesome, heres some of my thoughts though
Firstly i apologise for "stealing" your firues but they're awesome and im no good at photoshop so this is just paint...
Anyways..
1. We can learn a lesson from the romans when it comes to formation fighting, the reason it worked so well for them against the germanic tribesmen etc is that the tribesmen used big ass swords which need more room to be effective, the short roman sword allowed a tighter formation resulting in 1 tribesmen fighting like 3 romans. This same rule can apply to warband when the enemy (blue guys) use 2hs (in a FF server ofc). The dfficulty in WB is that stabs and overheads arent very effective because it takes alot more skill and precision to land a hit as aposed to a horizontal slash.
What i suggest is a looser formation, front rank sword/board, 2nd rank spear/board (they would have a sword though in case its needed), 3rd rank crossbow/bow(you didnt have figures for bowmen and really i wasnt about to make my own so they are designated with an A). As apposed to a line formation is need less people to be effective i think. The idea is to have enough space on either side of you to swing and not hit ur friends but not a big enough space for individuals to get flanked.
The 1st rank is there to "block the enemy", forward momentum is the key here as backpeddling will squish the ranks together, eliminating the room needed for effective fighting. The front rank as you pointed out shouldnt try to evade attacks but rather just block them (now this may make them vulnerable to kicks, ill get to that later) The first ranks job is to either push the enemy back or force them to stand and fight. Blocking is their main focus, ofc they should attack when they have the opportunity (even when fighting opponents with shields, you'll eventualy break it) but their job is to stay alive.
The 2nd rank, these are the opportunists, idealy there should be far enough behind and there should be enough space in between the people in the front rank for them to thrust effectively. Now unless your under heavy bow fire you can pretty much keep a thrust chambered because the front rank has thier shields up (this should make it harder for archers and because you walk at pretty much the same speed when holding up a shield/chambering an attk you can keep unit cohesion). As soon as you see an oppotunity present itself you thrust and hopefully stab the enemy (this can be when he's attacking, when he kick, when he gets hit in the back by one of his archers etc). Now it doesnt matter if he blocks it, because your there harrassing him, he isnt gonna have an easy time taking out your buddy in the 1st rank, you should eventually wear him down.
Now if the enemy charges your line in a close formation (i.e a bunch of guys all with shields up rush you) you will want to plug those gaps in your 1st rank as they risk being overwhelmed since the second line or spears wont be effective against a shield wall, the guy in red should switch to a sword and shield and move up into the 1st rank. Hopefully some of the enemy will backpedel (this always happens in pub matches), the guy in red can pull back into the 2nd rank. The key here is to not backpedel yourselves, counter thier charge then hold your ground untill the formation is back to normal then advance once again.
The 3rd rank is there to offer ranged support, now this may be a departure from the norm having the archers so close to the fight but the way i see it lone archers or even groups of archers far beind your lines are easy targets for flankers and enemy horsemen who will just ride around your main infantry force. The archers/crossbowmen can shoot from either side of the 2nd rank and then get back behind them for cover when reloading. If they are good enough and if the formation isnt too tight they can even shoot through the gaps in the formation. Thier main job is to try and take out enemy archers and harras enemies who attempt to flank, they should be rotating at all times keeping an eye on whats happening to either side and behind the formation.
2. Now what if the enemy flanks you? hopefully you have some cav to stop this from happening but if it does the guy in the 2nd rank can pull out his sword and turn to face this threat. Flankers should be a priority for the ranged units in the 3rd rank, they can swing out and target the flanker. Since he is busy with the guy in the 2nd rank his side or even back will be exposed, if he turns to block the arrow/blot the 2nd ranker can land a hit. Once the threat is nuetralise everyone returns to normal formation.
3. No picture....
Enemy cav, what do you do? well a direct charge shouldnt work. In the event cavalry charge you should have early warning if people are alert, if this happens the formation should tighten up, now if the second rank is good they should be able to thrust at the horsemen and stop him before he makes contact, if not it doesnt matter from which direction he comes from the horseman will be charging through 3 ranks this should stop him (unless he's got a really good horse) making him an easy target. The weak point is the rear, archers will be very vulnerable while xbows will be ok since they can whip out a shield (I Suggest that the 2nd rankers buy an extra shield at the start, droping one for the archers to pick up). Idealy your own cav should stop the enemy cav form getting right behind you. What if the horsemen swerve away as they strike? well you should be able to tell when they're doing that and pull up your shield and block the lance, and as the cav circles around for another charge the archers/xbows should be trying to take out his horse. Now if his horse does go down, unless its right next to the formation dont go charging at him.... big no no, your cav should be able to take him out since he's all alone.
I dont know if this would work but it would be great to test it as the logic to me makes sense. It is also quite do-able, the formation requires 7 people, in a regular 10v10 that leaves you with 3 cav (which should be enough unless they charge in and get themselves killed). The cavs job is to contain the flanks and make sure the infantry formation doesnt get surrounded.
Turning would probly be an issue but if the front rank all had the same emblem/standard thingy, the 2nd rank all the same while the centre red person had a unique one it shouldnt be too hard for people to get into thier positions relative to where that red guy is. The real challenge would be is if the entire enemy force flanked you while all thier ranged units held a certain point, this would mean that to turn the formation you've open up your side to enemy fire. The only way to counter this would be to hope your archers are better than thiers and take them out before enemy melee units close in or hope you can advance quick enough to engage thier archers.
Now if the enemy team is made up of small groups all roaming around indepently this may present the problem of getting "swarmed" with enemy ranged units all around you and infantry/cav charging you etc. Well that is why a static formation needs to be supported by cavalry, not a lone horsemen but an organised group of calvarly who really should be able to take out a small group of infantry.
At the end of the day formations would only be useful on certain maps but it would be fun to try it out.
We should definitely give formations a go, ill message ACC1 and see if we can organise something between rawr,KOS,AOS and SPLH we can rustle up 20 ppl no probs. Imagine Dojo and keens surpise if we could pull this off in a clan match.