ASW – Alternative hero leveling.

To summarize:
Regarding classes, as I said, they are only possible with a large number of heroes, which creates a dependency (link) with NHF. In my opinion, it's better to move classes to NHF entirely, since they don't affect skill progression changes, so discussing them here is inappropriate, which is what I've been trying to convey (if it's absolutely necessary, the discussion can be raised in the corresponding thread).
Regarding spell changes, that's a different topic, so that also creates a dependency. Starting a separate thread just for spells seems inappropriate.
None of this concerns this project.
Regarding the acquisition of more "desirable" abilities after less desirable ones (for example, the line: Blessing Giver - Seal of Darkness).
1) First of all, this is more of a spell problem than a perk problem (and spells are definitely not being touched for now);
2) Secondly, spell drops are a random process, and usually, we make do with what we have. In the event that a perk is needed after a master of a certain spell (when the spell is missing), we would take an unwanted ability, which is bad.
Let's look at an example.
What is countered most by darkness? Haste - by Slow, Smite - by Weakness, well, maybe Stone Skin by Disrupt. It turns out that Eternal Light after Righteous Wrath is more beneficial for the player to use, if it were located there. But in another case, we would get a very strong branch. A double-edged sword.
But in any case, Eternal Light must be made available for upgrading (if it's not available, a beautiful combo will be ruined), if not as the second, then as the third level. At this stage, we have Eternal Light after Master of Defense (Blessing Giver) at level 2, which allows us to upgrade both Wrath and Eternal Light and prevent Stone Skin, Haste, and Smite from being countered with some probability ;) Logically, the idea is sound.
Blessing is also countered by Weakness, but Weakness is weaker than Slow, Weakness, etc., and it's unlikely the opponent will cast it - they will cast a strong debuff instead. It turns out that Eternal Light after "Blessing Giver" is most beneficial ;)
Moreover, aesthetically "Eternal Light" protects against dark magic (i.e., "Gives protection") - which also fits very well ;)

Now let's deal with Seal of Darkness. Based on the above, it also makes more sense to give it after BG, but aesthetically this is incorrect, because in general, it won't protect, but only complicate the opponent's choice. That is, this ability can be anywhere.

Twilight. Dark and Light magic are native to Haven + it has little spellcasting (here, perhaps, there is Inferno, but Light is harder to get there, although, if you do get it....). It is logical to place the perk in racial abilities instead of Oversight (since the latter has already been removed). So most likely, it will go there.

Surprise Attack. Aesthetically (both in name and meaning), it is very accurately placed after Wrath (Analogy: 50% Initiative increase - Haste, "Attack" in the name - Smite). Now let's consider it in the game. The thought immediately arises: why is Teleport a Light spell and not a Summoning spell (since Summoning also includes "Astral" magic). But that's only half the trouble: if it were in Summoning, the ability would be hard to understand: it gives initiative, so it would look fine even in Logistics (like the devs have it), if not for the Light spell. Now consider how the spell depends on the strength of the Light school knowledge, and you might be surprised that it doesn't (o_O) (except that Expert can transport across city walls). Consequently, what is this ability doing in Light??? It turns out I just fell for the better aesthetics :(
Based on logical considerations, the ability must be moved outside of any magic school (aesthetically logical (if only partially) would be: Logistics, Leadership, and Attack).
Logistics. Essentially, it could be located after the speed aura. But increasing speed would make SA less valuable :(
Leadership. A triggered Battle Cry also shifts the unit, just like an enhanced Teleport. (It turns out that after teleporting, positive morale is automatically triggered). Cool.
Attack. "Surprise Attack" - the name itself favors putting the ability in Attack, but essentially a lot can be lost. And aesthetics are more important in meaning than in name, so even Light magic would be preferable here.
That leaves Leadership. Not many abilities are left in Leadership, although there used to be just as many :) Aesthetically it's logical to give SA after Inspiration, but again, SA and I are alternatives to each other, as they involve the hero and should not be acquired sequentially. Therefore, with the appearance of a new ability in that "school", the progression will need to be restructured ;)

Banishment. Aesthetically, Banishment is the essence of an Inquisitor, Wrath, and the fight against demons. It depends on mastery of Summoning magic (the formula is likely hardcoded in the "exe"), but it will increase by a maximum of 30% if fully upgraded. Why the devs put it in Summoning is unclear (only perhaps for a mage or Necromancer, more likely the former, but Sorceresses already have magic coming out of their ears). In Light, Banishment can be used at a minimum of 75%, which is also quite good. (Checked the coefficients - the dependency on Summoning can be removed, but it won't be possible to give a dependency to another school). But essentially, what benefit does it bring to Light?
No benefit at all :( It could be left only in an artifact, replacing the ability in the wheel with something else (I haven't noticed this perk being popular, so it wouldn't be a pity to lose it). Or try to make it an additional effect for Light magic, or move it somewhere else.

In total, there are only 2 second-level abilities for Light. Not much. Nothing should be given after Wrath (if 2 are left) because it is strong enough on its own. Seal of Light 100% goes after BG. That leaves Seal of Darkness, which essentially doesn't matter where it is. There is also Guardian Angel. This one can be placed (and renamed to "Last Hero" :) ) after DB for all races except Orc (fits aesthetically). However, there the angel flies onto the battlefield and waves its arms, so this still needs thought