Дегустация Horn of the Abyss

it's easier to leave only 8 necessary skills and make it so they always drop, why bother?

The game will immediately stop being interesting. It is necessary to actually rework the skills in detail, especially the least used ones (which are also the unpopular ones).
Here is an example of some reworked skills:
• Learning
Increase the values of acquired hero experience from 5/10/15% to 5/15/25%.
• Mysticism
Change mana regeneration values from 2/3/4 to 2/4/6.
• Literacy
Allows heroes to exchange spells of level 1 and 2/3/4, as well as copy spell scrolls up to level 2/3/4 into the book.
• First Aid
Gives control over the first aid tent to the hero, healing from 1 to 50 for the first unit in the selected group +
Basic level: no additional effects.
Advanced level: casts a basic level Cure spell on the group.
Expert level: casts basic level Cure and Joy spells on the group.

I've seen many arguments regarding the Eagle Eye skill. Indeed, it requires a detailed rework! As an option, the following could be used: add the ability to use a learned spell directly in battle.