What mixed hero class of the Haven faction do you like?

You can definitely turn a mage of Order into one. The advanced class is available. Why should it be excluded?

Archmage is a separate branch – any mage with 3 or more different spells can become one – and it’s not right to put it in the same row as classes that require 2 skill branches. For example, Illusionist is an Archmage, focused on Nature and Order spells; if you add any 3rd spell, he will become an Archmage.
It’s just that the choice becomes incorrect; if you choose Archmage, it surpasses all other magical classes, and the hero will definitely get it if he has more than 2 spells, while the other classes are for warriors who know 2 spells.

Added 3 minutes ago

You can definitely turn a mage of Order into one. The advanced class is available. Why should it be excluded?

Look, right now there are 2 equal leaders – Wizard and Archmage, but you can’t say that Archmage is better because if a Wizard takes one more spell, he will become an Archmage, meaning he’s essentially an underdeveloped Archmage.

Added 17 minutes ago

You can definitely turn a mage of Order into one. The advanced class is available. Why should it be excluded?

Hmm... so, the Enchanter, or whatever he’s called, the Illusionist – look, if there wasn’t an Archmage, those votes that are currently for him would go either to the Wizard or the Enchanter, but when there is an Archmage, of course, no one votes for the Enchanter, as the Archmage has the same bonus for all spells.