Added 3 minutes ago
[/U]Very often, Specializations are very powerful, so it makes sense to make it so that you have to choose between something, rather than mindlessly leveling up in the same branch to get to the Specialization, while having all the best skills.
First of all, it all depends on the map.
The usefulness of any skill is determined by the map, and any Specialization is insignificant compared to the combination of schools of magic and "defense"/"attack" if there is an opportunity to use them (depends on the enemy faction).
For example: The Tower Specialization is basically useless against 300-500 dragons (compared to the number of neutral creatures on a difficult map with the possible increase in the player's army from one castle by that time), but the combination of "defense," "light," and "dark" magic can defeat them without losses. If the Tower Specialization requires "fire," "logistics," and "education," all three necessary skills cannot be leveled up.
2.
And the absurdity with the Demon and Tower Specializations needs to be addressed (as I wrote above - the Tower worships the God of Darkness, but for some reason they level up Chaos, and vice versa - the Demons worship the God of Chaos, but for some reason they level up Darkness).
You need to understand that the developers were guided not only by the logic of the world's description, but also by the logic of the game's balance. And if you don't want to get just a "pretty picture," it's worth considering this.
P.S. I'm not very knowledgeable about the world's history, so I even googled it:
Info (I don't see where the spoiler is here):
>>According to legend, it was created by Ashha - the Dragon of Order or the First Dragon (it is known that Ashha is multifaceted - different peoples of Ashan represent her image differently; for example, Necromancers worship her as the Spider Goddess). Ashha also gave rise to the elemental dragons: Elrath (the Dragon of Light, worshiped in the Griffin Empire), Malassa (the Dragon of Darkness, patroness of the Faceless and Dark Elves), Ilath (the Dragon of Air, worshiped in the free cities of the East), Silanna (the Dragon of Earth, corresponding to the race of Wood Elves), Arkat (the Dragon of Fire, worshiped by the Dwarves), and Shalassa (the Dragon of Water, worshiped by the Nagas). In addition, there is the Dragon of Chaos, Urgash, Ashha's brother, who opposes her and seeks to destroy everything she created; Urgash created the demons<<
So what? What is the connection between "chaos magic" and the god of demons?
There is Ashha - the dragon of order, and there is her brother Urgash - the dragon of chaos (in this case, the word "chaos" does not refer to magic, it is just opposite names).
Because "chaos magic" is the elements of "earth," "water," "wind," "fire" - the elements of Ashha's dragons. It would be more correct to rename "chaos magic" to something like "elemental magic."
And before you change anything: you know why demons need "fire magic" (damage magic) when leveling up 45%/10%/15%/30%
3.
No way!
Leveling up all three lords on the way to the Specialization - isn't that too much? In general, it would be better to make it so that it is impossible to level up all the lords - max two.