What I worry is that it's bandaging two systems together: that whatever mechanic is used for combat, some players will just want to do the fighting and some will just want to do the social bits and each will feel like the other piece is a detraction.

How does the social interaction look like ?
Are things happening outside the battles, like in dungeon keeper where units train and sleep and if they do it effectively they ll be ready for combat when it occurs,

or is it more of a few extra settings while re-equiping the characters ?

(or are they happening through a story that's to be followed ?)

You could just give them all a single "directive" pre-battle, aka :Try not to get carried away in your rage/don't come into a fight or antagonize (character)/...

a character could also get so much support/cover from his team(because of their directives) that he can be given a directive to focus(boost) a combat-stat like accuracy.

@Acharis:the mechanic focused on IS team-management, whether this is realistic only concerns setting, which is fantasy.

Interpersonal conflict definitely has an effect on soldiers, if only by increasing stress levels. A quick google search suggests this is a topic the military researches and trains its officers on. I agree you're unlikely to change tactics over it. On the other hand, I'm certain you take relationships into account when pairing up soldiers for fire teams or choosing whether to reassign an individual.

I disagree that playing up conflict management is less real then the usual approach of treating soldiers as interchangeable cogs. Commanders, especially at the lower levels, spend comparatively little time focused on the enemy. It's training and logistics and stress management and paper work and all that stuff. It's a job. In games we tend to abstract away logistics and focus on throwing tanks at each other. I don't think playing up the social aspect of a band of soldiers is less realistic than waving it all away, it's just caricatured in a different way.

I also wouldn’t assume that “good teammate” is in any way the default setting for a professional soldier. “Good teammate” can very frequently be in opposition to “don’t die.” Let’s take the mortar team example: Firing the mortar clearly reveals your location. Stopping the mortar is a high priority for the enemy. The mortar team is busy and underequipped and can’t properly defend themselves. Do the other soldiers in the area fight to the last man to protect the mortar team, or do they scatter when the battle turns a little? Does the mortar team keep firing as conflict gets close, or do they figure “the other soldiers are going to scatter, let’s abandon this right now?” The self-interested mercenaries are out of there immediately. The other soldiers have to like the mortar team somewhat (or be very professional) to stick around and give them proper cover.

How does the social interaction look like ?
Are things happening outside the battles, like in dungeon keeper where units train and sleep and if they do it effectively they ll be ready for combat when it occurs,

or is it more of a few extra settings while re-equiping the characters ?

(or are they happening through a story that's to be followed ?)

You could just give them all a single "directive" pre-battle, aka :Try not to get carried away in your rage/don't come into a fight or antagonize (character)/...

a character could also get so much support/cover from his team(because of their directives) that he can be given a directive to focus(boost) a combat-stat like accuracy.

What I've currently got sketched up is a network of faces, with red or green edges between them. If you click an edge, it might display a description: what are the strengths and weaknesses in this relationship. If you click a face, you can see the characters stats, equipment, history; and some little boolean personality traits. "Slow to forgive", "distrusts new recruits", "loves spicy foods". You'd probably have a way of spending influence to encourage friendship from this screen, or try to give/remove a trait.

The interactions themselves, I'm currently leaning towards random events. Characters announce they've begun dating, break into fist fights during training, have a wild night at the tavern and you're run out of town. I want them to be flavor heavy: a lot might have little in game impact, but help create a narrative to what's going on. You'd often be given options on how to handle the event, with different tradeoffs to each. Some would change your relationships with the factions who can give you contracts. The actual events would be triggered by various stats in the game. You'd also get notified if somebody has been performing better in training (leveled up) or stuff like that.

Combat I keep changing, but I'm currently picturing an animated brawl, with iconography to show how the battle is going. Arrows display who's fighting with who, little gauges show who's got the upper hand. Over to the side is text describing any particularly noteworthy events. This text would give a sense of how the social network is changing results: George shouts at Harry "What the hell? You're supposed to have my back". Sara and Dwight pull off a rehearsed routine and injure an opponent. He should be out for the battle. I'd color code those to convey when something that encourages bonding happens, and when they've gotten mad at each other. You could click commands on the side, or by clicking a mercenary, to change tactics. Different commands and tactics would be more/less appropriate based on the makeup of your army and their relationship. There would be occasional events in combat related to the network: characters would react to friends dying. If they happen to meet the killer of a friend in another battle, they might make some exclamation. Old friends suddenly on opposing sides might only lightly spar.

Outside of combat, you'd set the battle orders, possibly muliple formations. You'd have boxes for each position in battle, and would drag characters over. The boxes would change color depending on compatibility with the neighbors. I'm considering having two dimensions for compatability: opinion and trust. Even if two characters dislike each other, they could come to trust each other in combat. On the other hand, a veteran might really like this new rookie, but he's not putting his life in his hands too quickly. Characters would have different roles they excel at, in particular 1-on-1, 2-on-1, or 1-on-2 combat and whether they stand routed to the ground or dance about. This I picture as sort of like a very simplified Football Manager tactics screen. You'd usually only tweak tactics, filling in for an injured mercenary or pushing two apart who've gotten a little hot.

You'd sign a contract, deal with events on the way to the battle, view your opposition, maybe tweak your tactics, manage combat, deal with the outcome, possibly travel somewhere else, and repeat. The contracts themselves would tell stories, with a series of them chaining together to tell of wars, etc. The little random events would tell other stories about the lives of your men.

If combat doesn't occur on a real map it would replace the formation/position entirely with jobs (guard the group/ be leader / guard person X / seek out enemies / supply the others with potions etc).

Expanding on the idea, maybe the player could send out multiple parties at a time, some for an important mission, others more to gain experience/bonding.

A problem is how do you judge the effect of the various carrot and stick measures you can employ? Are there consequences which are not undoable (you misread and lose a valuable asset or weaken your 'team' simply because its too random/arbitrary/intricate to figure out...)

So any complicated mechanism would have to become a significant component of the game play (otherwise its just scheduling goodies/strokes to keep each characters 'happy' bar sufficiently high --- which might be a sufficient game complicating element ... but one more thing to do maintenance on - like maintaining ammo levels).

Agreed. I think that will require playtesting. My hope would be that by keeping the system logical and straightforward (e.g., spending points to improve the relationship between two mercenaries never somehow makes them madder at each other) the player can make progress at what he wants. Perhaps there's a better way (A is best friends with B, B is reasonably close with C, maybe improving the B-C relationship will also bring A-C together) for advanced players to figure out, and solving any one problem isn't necessarily solving the biggest problem, but at least the game responds understandably to the the player.

If that's not the case, I could also see having a 'preview' button for actions, or an automated evaluation of a formation, or providing exact numbers on effects, if playtesting suggests the players are thrashing around blindly.

If combat doesn't occur on a real map it would replace the formation/position entirely with jobs (guard the group/ be leader / guard person X / seek out enemies / supply the others with potions etc).

Expanding on the idea, maybe the player could send out multiple parties at a time, some for an important mission, others more to gain experience/bonding.

Good suggestions, I'll have to give them more thought. The numbers seem vitally important to getting the design right: too many units and you lose track of the individuals, too few and the social network is simplistic. Too many in a fight and you've got little margin for injuries/reserves, or opportunity to focus on individuals, too few and the rest of the team is extraneous. Multiple parties could be a good different approach if the numbers aren't working right together.

Another idea that connects emotional well being and has a go at tackling the issue of troop not performing well in combat:

In general, you could have those emotional statuses that other people have mentioned, but I think it would be better if negatives and positives came into play primarily outside of combat. So if every unit has a collection of numbers which influence different stats, have them be affected outside of battle. If you put Alex the new recruit with Brom who hates recruits, then he'll have a debuff if they've been together for long enough outside of combat. Or maybe two characters are preoccupied, which lowers their attack for x amount of time. But all of this factors into the battle going in, and just becomes something to manage at the start of a battle. You're dealt a certain number of cards, and you manage your hand out of battle, trying to prepare the best setup possible, but it becomes something static to strategize around once you get onto the battleground itself.