Definitely. Separate attacks for separate soldiers (even if it happens at the same time, with the same click, due to being one unit)

Also, even a minor troop setup/ relocation would be better than 'forced' auto-troop setup. A decent starting distance between armies would also be nice.

Ofc, to me the size of a tactical battle-map would depend on how  late-game is handled.

Will late-game be handled with a chess-style strategy battle consisting of small skirmishes of 200+ soldiers each? Or would a "big battle" (of how many soldiers you can have in an army) ... all on one map?

If the former (Option A), I could see Strategy map archer barrage and seige barrage added in (with seige being more useful ofc, and only once per turn no matter what combat speed, and archer barrage being much weaker than a normal in-battle attack) as well as an eventual Cavalry Unit withdrawal/retreat system being added in as well.

If the latter (Option B ), then I could see much larger battle maps, (with armies starting farther apart) with customized troop deployment, and a much larger logistics max than 10 units.

another thing is depending on "how many soldiers you can hire" vs "how big an army can be"

For instance ... if army limit is 100-200 and soldier limit is 2000+ ... then probably the Option A. However, if the army limit is 100-200 and soldier limit is 300-500, then probably a non-expanded Option B.

If we consider the moving of various armies on the Strategy Map the "Macro Battle" and a singular Tactical Battle as a "Micro Battle" ... then I'm basically saying there are two ways to do this (presumably with mods that expand the scope and populations).

1. Focus on the Macro Battle to make the use of multiple Armies more interesting.

2. Focus on expanding the Micro Battle, in the pursuit of having a singular "Massive Tactical Battle" be the epitome of late-game warfare.

If you go the first option, there are actually a lot of interesting things you can do. For one, you can make Seige Weaponry excellent on the Strategic map and Sluggish on the Tactical map (2-3 turns for a single attack).

In addition, you could make switching to Wagon-Packed -> Combat Teady for seige weapons be a manual action that takes a full strategic turn. Getting caught in a Tactical Battle with a Wagon-Packed seige weapon would be like having your pants down ... the units would be worthless and take, say at least 5 combat turns to assemble, and another 3 turns to fire (if we're talking Trebuchet).

With this one gameplay addition, it would result in "seige armies" being kept out of Tactical Combat and buffered by Melee Oriented armies and perhaps flanked by Cavalry oriented armies.

Of course, a robust and effective Area of Control would need to be in place for fringe armies to properly buffer the siege batteries. Also, the clumsiness of Siege Weapons would make battle-ready Siege Batteries extremely slow on the Strategy Map (and tactical), making them rely on the rank and file soldiers to defend them from the enemy.

In a prolonged battle, these Siege batteries would be "weapon emplacements" that the other Armies would have to Maneuver around in order to defend them.

Meanwhile, ranged weapons "barrage" would be like a fly-swatter compared to the damage they can deal in Tactical Combat, and only be useful in MASSIVE numbers or against an opponent that has minimal armor ... and either way the effect would be much reduced upon units with shields or some other natural protection or dodge ability. And with a range of no more than 1 tile for most Bows. (while a trebuchet would have a max range of at least 2 or 3 tiles ... but a permanent 1 movement while not packed inside a Wagon)

So basically ranged bombardment would be able to "sting" opponents, while the main punch would come from the Heavy Weapons.

Another neat trick for the first option could be for Mounted Units to ignore the "Only Champions retreat" policy ... or at least after some Tactics or Logistics tech is researched. In this case, Mounted units could literally "Punch In" for a quick Hit-and-Run skirmish, taking advantage of a foe's potential lack of mobility. One particularly harsh example would be to "Punch In", destroy some Siege Weapons, and run away saying "sayonara."

It would also be useful if your opponent had Massive Armies of slow peasants, and you had Smaller Armies of Mounted Units.

Now, retreating from a city-battle is a pretty useless option (even for the attacker), so the slow army could still win the numbers battle by inch-worming to each opposing city and either razing or leaving a sizable garrison.

Another block for abuse of this strategy is that mounted units wouldn't be able to breach the walls of a city (I guess unless they had a powerful destruction caster ... but then thats magic not logistics ) ... so without an army of Melee(w/ rams or ladders) or Heavy Weapons (or Magic) the Numbers guy won't have to worry too much about those pesky raiders stealing his own cities.

Another interesting thing with either option would be to have "command talents" ... with each Champion having some level of inate commanding talent, that can be increased by Academy training, command experience, and level-ups in different ways.

(level-ups can include increased Charisma, and certain Command-based traits and abilities that require either a certain amount of either Academy training, Command Experience, or Charisma rating)

Academy Training opportunities could depend on Tech Level (and how upgraded your Academy building is ... if you have one). This would be based primarily on tech level, and require the Champion being in a city with a Military Academy. There could be a couple stages of Military Academy upgrades.

Academy Training could allow your Champion to use various new formations ... and the higher level the Academy + the higher your Warfare tech level, the more formations are available.

Command Experience could effect a "command level", and this experience should only increase if the Champion is the general of the army and combats with a particularly numerous foe OR any foe from a primary or minor faction. The command level of a Champion could determine the strength of each formation. Formations could be stronger (or simply increased effects). For instance, a low Command Level could have Testudo formation give some increased Archer block, and some attack penalty. Meanwhile, a very high command level could have Testudo formation give ALL archer block, and NO attack (and a higher over-all defense bonus).

Then, traits gained on Level-up could effect mainly Morale and Army Maintenance. For instance, "Logistical Mastermind" could be a certain trait that requires a VERY HIGH Academy Training rating, that greatly reduces the maintenance of any army he commands. Or he could buy "War Hero" which requires a certain command level (from commanding multiple victorious battles vs Faction armies), that greatly increases overall morale.

At the opposite spectrums of Academy Training and Command Experience, you see two radically different strategies. One relies on vast amounts of troops using a HUGE library of Combat Formations ready for ANY situation, and the other relies on highly effective "elite" troops using basic formations.

The latter could still field huge armies if he wanted, but the Maintenance would be much greater, so the War Hero would wish to focus on leading a smaller army of hardened elites ... with near un-ending morale.

// If the adventure tree includes unveiling the location of rare metals (perhaps with limited deposits), then the War Hero could focus more on Adventure than Warfare, and have a small, elite army ... while the Tech-Master Academy "by the book" buy would focus more on Logistics techs and Academy techs In the Warfare (and possibly Civilization?) tree.

In an extreme example, the War Hero could be leading some elite units + Champions with the 4 Swords of the Armageddon, in Death Armor, against a large army of musketmen, Cannons, and halberds.