How should I use Custom Campaign?

[Spirit_of_Currents]

I can create armies and factions with Custom Campaign add-on, but I don't know which units I should include in which armies.

I want to create armies in which every max-level unit allowed is somehow useful. I'm asking for help because I want to use the same armies from the beginning and I don't have much playing experience. The only thing I know now is that I should put those units only able to level up once in the same army. I should also include for example Spearman in that army because its tree has a branch which ends at level 2, and I should allow it only level up to Javelineer because level 3 units would make those units with only one level-up useless. Perhaps this only information I already have is wrong.

I only want include those units recruitable in Default, plus Dwarvish Scout, Mermaid Novice, Sergeant, Thug, Young Ogre and that level 1 Orc with leadership, in my armies. I want to include every max-level advancement of those units in exactly one army (I mean possibly in the recall list).

I already know how to make factions for the computer: First, I put every unit I want the AI being able to recruit in the same faction. Then I do some testing on the map (Silver-something that has a petrifying Tentacle of the Deep in the northwestern corner) several times (I recruit nothing but I have all 48 units in my recruit list). Then I pick those units the AI recruited most, put them into a real playing faction and remove them from the testing faction. Then I repeat until everyone of those units is in a real faction.

I still have only made only one real faction, and it would be nice if someone knowing the code of the 1.10 AI could easily tell AI's importantness order of units.

[SigurdFireDragon]

Just wanted to let you know I've seen this, hopefully I should have an answer for you in a few days. Though I'm not 100% certain what it is you are asking.

EDIT: Here's my answer.

I want to create armies in which every max-level unit allowed is somehow useful. I'm asking for help because I want to use the same armies from the beginning and I don't have much playing experience.

Unfortunately this is something of a playing experience needed for answering this part. While I have a good bit of it, 99% of my use of Custom Campaign has been using it with factions from eras as is, with maybe a hero unit or a special leader. I've only done custom armies twice, once was with the Undead by replacing Bats with Skeleton Riders, and Dark Adepts with Elvish Shamans & Elvish Nobles/Lords. The other was a complete attempt to make a custom army, which didn't work out too well. The question you're asking is a bit involved, I'd recommend looking through the How to play series to get a sense of unit usefulness in various situations.

Assuming your question is about avoiding having two different level 3 units in an army, one of which is has worse stats than the other, that can be accomplished by comparing the stats at http://units.wesnoth.org/

The only thing I know now is that I should put those units only able to level up once in the same army. I should also include for example Spearman in that army because its tree has a branch which ends at level 2, and I should allow it only level up to Javelineer because level 3 units would make those units with only one level-up useless. Perhaps this only information I already have is wrong.

I'm gonna say this is not a good way of looking at armies in Wesnoth. What you want to level a Spearman into is situation dependent. If you're currently playing a big battle against Drakes, Javelineer (with a pierced melee & ranged attack) or Pikeman (with strong melee pierce) are usually both preferable to Swordsman. If that same Spearman is in a battle versus Undead, Swordsman is usually the better choice, as Skeletons are more resistant to pierce than blade attacks.

Another thing to consider is the army's efficency in a variety of circumstances, and in future scenarios. When I started playing, when using Undead, I'd always prefer to level Skeletons to Revenant / Draug because of leveling-up ability, but now I prefer to have a mix of Revenants & Deathblades on my recall list, to maintain flexibility for a scenario. Also, it can be useful to have units that don't go to level 3, as you don't have to worry about your upkeep cost increasing as much during a scenario due to leveling, so you can afford more level one units, or save more gold during the scenario.

I only want include those units recruitable in Default, plus Dwarvish Scout, Mermaid Novice, Sergeant, Thug, Young Ogre and that level 1 Orc with leadership, in my armies. I want to include every max-level advancement of those units in exactly one army (I mean possibly in the recall list).

Not sure about this. Do you want to add these max-level units to the recall list, or add their level one counterparts to your recruit list? If you mean to make several armies, and add max-level units to their recall list and not repeat any unit in any other army, and all the units distributed still be useful, that's a bit of a challenge. It seems like it should be easy enough distributing some of the units based on special abilities, but other aspects might be more tricky.

I already know how to make factions for the computer: First, I put every unit I want the AI being able to recruit in the same faction. Then I do some testing on the map (Silver-something that has a petrifying Tentacle of the Deep in the northwestern corner) several times (I recruit nothing but I have all 48 units in my recruit list). Then I pick those units the AI recruited most, put them into a real playing faction and remove them from the testing faction. Then I repeat until everyone of those units is in a real faction.

I still have only made only one real faction, and it would be nice if someone knowing the code of the 1.10 AI could easily tell AI's importantness order of units.

I'm not that knowledgeable about the 1.10 AI code, but know enough that it doesn't have good decisions in several cases. One example you can see for yourself is to run your recruit test with the computer playing the Loyalists, the AI will almost never recruit Spearman, the only time I've seen it do that is if you have some Drakes already on the map, then it will start recruiting some. This is bad, as the Spearman is the cost effective damage dealer for the faction.

To make it use Spearman, you would have to adjust the recruitment_pattern for the faction in Custom Campaign to have more occurrences of fighter, and remove other units that have usage=fighter from the recruit list, until you get a mix that you are happy with.
A better way would be to update to Wesnoth 1.12. When running the recruit test here, the AI does better, incorporating Spearmen in it's recruit, along with less of the expensive & fragile Mages.