A huge amount of attack is half the battle, and considering that the riders also break through the enemy's defense, you can immediately forget about one enemy unit. The main thing is to manage to attack.
Furies also bite very hard and are fast, so they are quite good at mowing down slow enemies.
Ents can be killed with the same furies and riders, or with anything else – there's nothing special about them.

At the beginning, you can use only furies or hunters.
And if we're talking about it, it's better to have at least a combat mage, rather than a pure mage, because wasting all your attack points is not very good either.;)

The most combat-oriented mages are Iranna, Weinshan, Kifrah, Sorgall, and Erin. The rest are much more mages than fighters.

Unless it's just because of their special abilities. Primary skills grow at the same rate.

You can't create a warrior-mage for one simple reason: even with low magic, a Warlock casts spells, rather than shooting.

And why is that?

By the way, I recently played... the skills turned out like this:
8 - 7 - 6 - 3
What's wrong with that being a warrior? :)