Whoich faction has the most different effective tactics/setups for it?

[cbinetti]

The Elves to me have great tactical flexibility. They have such good archers that they do not need to rely on melee support as much as the other four factions. They really do not need their healers, unlike the Empire. Their mages are rarely the unit that you build the army around, but they have their roles. I like Skylords too, allowing you to forgo traditional melee units if you want. The Elves might even be the hardest army to predict. I think that multiple squads in an Elven army are very effective because of this effective diversity.
The second most diverse faction in terms of army setups and effective tactics is the Mountain Clans, which I call the Dwarves a lot. This is misleading because Yetis and Giants make this faction very competitive and they are not Dwarves. I like Yetis a lot, because they help out a lot early in the battle and make up for the lack of mage non-hero units early on. Also, I feel like they are useful for most of the battle if not all of it and they are great for garrison forces. Giants are great and lessen the need for melee infantry if necessary. You can have Giant mages and melee Dwarves or melee Giants and Dwarven mages, but you could have both of each category. Also, you could have flamethrowers or traditional ranged units, but Dwarven ranged units for me are often underwhelming unless used to fill a role, like Elven mages. The Tenderfoot branch to me is the most controversial, because if you can get your Tenderfeet to level 2, either branch, they are good, but if you cannot, they really only hurt your effort. They cost more money than a third melee unit or a ranged unit in a starting squad but they contribute much less damage until level 3. Tenderfeet make you lose damage for your squad until lvl 3, and then they become a net positive to your damage. they also do not heal but at least at level 3, one ranch gets cure, which is great. I have not always had success with them, which makes me think that they should be reinforcements to a squad, like the fourth trooper in a level 3 hero's squad.
Overall, Dwarves are almost as tactically flexible or diverse as the Elves. The other three factions are in a lower tier in this category. Let us look at the tactical weaknesses of all three of the factions-
Undead- They have no single-target ranged units of any sort except for mage units that are role-changed into ranged units. I do not like giving up one of my strengths just to have a tactical option. The Undead have two end-stage mage units that are not mage units and they are similar in many ways tactically. The other two mage units are the classical mage unit, which to me is superfluous when you have locked Initiates and the Elder Vampire. In other words, I feel like the mage unit tree does not add to your tactical options that much. Werewolves I think increase your tactical options, but they are very expensive. I like locked Fighters and Dark Lords but Phantom Warriors are viewed as a great tactical option. I disagree, preferring locked Ghosts or Spectres. One big problem with the Undead is that they need Paralyzers in the unit, which means less room for AOE units, which we need. Wyverns can be tons of fun, but they are better in bigger squads, where they make up for a lack of melee or mage units.
Demons/Legions- I find this faction frustratingly tactically inflexible. That probably sounds weird to hardcore Demon players, which I am not. Well you have strong but boring regenerating infantry. You have loads of bulky big guys, that crowd even large squads. You usually want at least one AOE unit and the AOE big guys units you have are not that good an too expensive and hard to get. You can go for the mage leader, but the Counselor adds more to your army tactically. Like the Undead, it is easy to have no single-target ranged units in the army at all. Unless you have two squads in your army, which I like to do with all factions, you will often have no single-target ranged units, which is a big tactical weakness. Your Demon units are in my opinion not so great, I like Fiends better. Gargoyles are nice but can be tactically inflexible. In starting squads, it is hard for me to be successful without an aoe unit or leader. So, in four spots, including the leader, you need one mage, one tank, and one big guy. That puts a lot of pressure on your choices. I also think that in terms of mages, Doppelgangers and Modei are hard to justify, meaning that in addition to locked Cultists, you have either Incubi or locked Witches of Hags of maybe Succubi, which all tactically do largely the same thing. However, it is hard to justify these advanced mages in small squads. You need at least four troopers in a squad to include the non-damaging mages.
Empire- I think that you could argue that the Empire is the least tactically flexible of all factions in terms of setups. They rely on healing way too much. Their melee units badly need the support because they have trouble with their hitpoints. Their ranged units all do basically the same thing, their mage units are not that strong and many of their high-level melee units are not very good. Titans help, but often one could argue that you are stuck with a relative dull set of tactical options. You need at least one healer, maybe two in a large squad. So, you have one more backrow unit and three melee guys, That is pretty stale, although there are a couple of options. For one, forgo the obvious aoe healers and go with a strong singletarget healer or two and a Titan. Also, the Witch hunter branch is pretty nice. But overall, I thin that the Empire has even less tactical options than the Demons or the Undead.
What do you guys think about this?

[QWEEDDY2]

In general, perfect party - "empire style": support(-healer is op), AOE mage, target DD - back line, 3 tank units - front line. With some variations for good doble-sized units of some factions and leaders.

But destroing Capitals require more specific parties for Undead, Legions and Clans.

[cbinetti]

The empire style is not tactically flexible it is one tactic all of the time. Most capital cities are meant to be impregnable. When the Guardian has 90 percent armor and 250 damage, you are not supposed to be able to conquer the capital. Capital-conquering is only for certain missions in campaigns and certain scenarios. Where the Capital Guardian is meant to be defeatable, the Dwarves do fine.

[QWEEDDY2]

Any party must have AOE. Any party must have elemental attack. Any party must have good one-target DD - better if he can do damage to any unit (archer-type). So Empire and Alliance - easiest factions even for Capitals.
Plus they have healers and low XP requisitions (expect elves centaurs) = overpowered at early game (against neutrlas) = fast and low gold cost map expansion.

They weakness - they double-sized special units. There is no space for 2x tank unit. Even demons Fiend better - he at least have poison attack (but Tiamat or Gargoyle far more better for demons party)

In Disciples 2, any Capitals can be destroyed starting from 2-3rd missions. Just keep defense potions that usually placed on map for some special party\cities (like Ork King in 5lvl City). Well, absolutely all scrolls and potions - for capitals. Any optional or quest enemies must be defeated only with magic book and unlimited staff's.
Also, very important to buy all spells from Magic Towers. its only things that AI can take before player (healing\resurrecting potions not important). And if more than 1 Capital - better take Clans->Empire->elves and later Legions\Undead.
Resources ans spell for destroying enemy - are random... or bugged.

[QWEEDDY2]

Only mage leaders can learn "staff-and-scrolls", except any created in Editor (u can edit save in editor and place a new Hero on map and he can be exported usually). Plant Rod - not a leaders, they same as Thief's. Even in Disciples 2 where they can upgrade leadership to maximum (in D1 they cannot do this). Rod planting cannot be added to others heroes in editor. Maybe only Empire and Elves plant roders can be interesting in some case (just for fan playthrough)...
Mage is better for campaigns... 100% for Empire. For others - only if mages do not have abilities (like empires mages). For some factions better Warrior hero, cause he didnt take important place of some faction tree unit. Im dont remember exactly every units...
Also, Flying is better than path-finding(i mean rangers heroes). So if u need fast courier - choose flying hero.
Elven mage hero - only one mage who flying. And absolutely all units in unit tree (last lvls) have special attacks. So even with shatter mage - better use mage hero Dryad as mage unit in party (frozen archer as target-DD, healer and armored centaur).

Capturing Capitals or not, anyway must important things in battles in Disciples - surviving of all units. So armor and HP - most important things. Elvens centaur tree give to player choose: armor or armor shattering (Critical Hit counted from full attack that unit can make, no defense mutter). Armor is better. Same as armor is better than HP or wards.
In campaign u can stay pre-existed one centaur and choose another in unit tree.

In Disciples 1 for Empire must-have warrior - Paladin. Then Inqusitor with Mind ward. Angel - strong attack unit and so not useful like Paladin. In Disciples 2 Angel completely useless - Avenger is better. 2x attack always better than +100% attack points. Almost same for Clan support unit.

[QWEEDDY2]

In case if u dont know (or anyone who read this)
Staff's are unlimited. Almost same for Talismans (4 using and 5 is last, but reloading reset this as i remember). AI dont use Orb's as i remember, but use Talismans. Most useful Talismans - vampire healing and ressurecting.

Any additional-attack artifacts (soul crystal with paralyse) have own %chance that not changed by any booster. Artifacts like soul crystal almost do not work for mage units. But very well work vampiric artifact. Undead Nosferat is very strong Hero at campaign end. He even can clear the 6-7 missions map without any unit in party. Strongest enemy (fat with huge HP) and count of them in each party - are easiest for Nosferat or mage with vapiic artifact. But Nosferat for fun only - very weak at start (not useful outside campaigns) and "not-elemntal" Death attack.

[QWEEDDY2]

Thief's chances sometimes counted twice. When player steal items from store\enemy item level (cost?*) counted as well. Same for some other guilmaster actions... Enemy level\city level counted before action and showed on scroll, as i remember.

*As i remember it differ parameter for each item that places somewhere if DBF archives same place as item characteristics. Sometimes it probably differ than item cost. Anyway, stealing chances for "atrifacts" lower that for potions; healing potions have higher chanes that resurrecting.