Mistakes when playing as Humans.

Recommendations on what not to do when playing as Humans
1. Take the skills of Sorcery, Summoning, and Chaos Magic.
2. Assemble a super-skill set.
3. Don't take Leadership and Attack.
4. Don't take magic at all.
5. Build a fort on the 1st week.
6. Immediately upgrade swordsmen and archers.
7. Build a Mage Guild of level 4 or 5 before building angels and knights.
8. Build training grounds early.

Let's go through the points:
1-2. These are simple and correct observations, but some people forget about them.
3. This is true for not all maps, as often the game is played with Machines, so without Leadership, Logistics and Magic can be decisive (if there is a place to buy spells). And there is also Education, Luck, and Protection (specifically for the race)... The combination of Attack + Leadership is a matter of taste and for достаточно высоких уровней, although, of course, it is quite effective.
4. Magic is not taken by knights on fast maps. Take it on Former Friends and see what happens if you need to be in the center on the first week. And it is very likely that you will have to fight enemies there.
5. +1
6. How wrong you are. Archers are definitely upgraded immediately, and swordsmen on a good half of the maps. Yes, it's very expensive in terms of resources, but the combination of archers + armored units is very cool. Archers deal significantly more damage, and armored units not only have 1.5 times more health, but also have a Large Shield, which is extremely useful against archers, who attack earlier than yours. Add a Tent to this group, and you are ready for work and defense. Therefore, you will recoup the money and resources. Of course, if the map is not too poor, then we do not upgrade swordsmen.
7. I agree. This guild can generally be left unfinished; it is better to look for spells on the map. If there are none, then you can finish it after the troops.
8. This is more of an exotic strategy, but it is quite acceptable on maps where you need to quickly break through something strong and grab the treasure.

Barbarians: Don't take Dark Magic.

Demons: Don't take Light Magic and Enthusiasm.

In essence, this is true, but if you take magic late and see that you have a good protection against Darkness from artifacts and skills (against Berserk, Blind), then you can take Darkness. It is very effective against demons - mass curse, and the demon deals 1.5 times less damage. And even more so at high levels.

Knight: Take Rutger as the main hero.

The hero is generally good, or do you just not want to give Dugal and Vitya to the enemy?

Necromancer: Take Empathy and Dark Magic.

In my opinion, Empathy is generally useless; you can't cast it much, especially as a knight. And does anyone take Darkness against a necromancer? Unless with Sandro's Cloak.

Ranger: Don't take Dodge (General), don't take Resistance.

These are useful perks, but there are many other useful ones: Tactics, Storm Wind, Retribution, etc.

Dwarves: Don't take fire resistance!!!

If you are sure that the dwarf will be able to and want to use pyrokinesis on this map, then yes. But he won't be able to do it everywhere.

Warlock: Don't take Reflection and Resistance.

And why take them? There is almost no point in them. This is debatable; some believe that it is better to reduce damage at least a little, while others believe that it is still useless, it is better to put levels into other perks and try to kill the warlock's army faster. But it definitely doesn't work against hit-and-run tactics.