Should I take the Wisdom skill?

The question about Wisdom is interesting. I would agree with the previous speakers regarding the size of the maps and add a little more. On Large and Extra Large maps, Wisdom is essential; for Medium and Small maps, it depends on the situation. Of course, this applies to a challenge, not a battle against the AI on the easiest difficulty. I conducted some experiments a few years ago where I deliberately didn't take Wisdom. Naturally, I chose a warrior-type hero for this. I still took Expert Magic, because I didn't want to give up Haste, Bless, Blood Lust, and other spells. In the end, no matter how I combined the other skills, I often found that magic was lacking, and the longer the game went on, the more noticeable this became. No, you can replace Wisdom, of course, but I wouldn't recommend it. Wisdom, combined with high-level spells, provides flexibility that you won't get without it. All that an Expert Elementalist can do without Wisdom is buff the army – simply increase stats and nothing more. With 3rd or 4th-level magic, the number of tactical options increases many times over. So, take it.

When leveling up, I take a new skill. If the levels increase quickly, i.e., at the beginning of the game, I do so. If the hero is already well-developed and there is a high chance that I won't have time to max out this new skill before the end of the game, I prefer to upgrade an old one.

Added 2 minutes later

why aren't you playing yourself?

Querty, you're a two-timer :)