I really like Dugald. He has a very good starting point.
If I manage to, I develop him to level 21 (usually the game ends at level 20-21 for me) like this:
Expert Counterattack - Experienced Tactician
Expert Offense - Archery - Battle Fury - Retribution
Expert Defense
Expert Leadership
Expert Light - Protection - Righteous Fury
Developed Logistics
Regarding machines. I think it's not profitable for humans to use them - Retribution is better. Unless the opponent is a Necromancer.
Humans' ballista is not very strong. After all, its damage calculation takes into account knowledge and attack, and humans develop knowledge slowly. The ballista is only good for Orcs and the Demoness Deleb.
It's not quite clear against whom such a build is effective. Or is it against everyone?
Leadership, logistics, and defense should still be fully developed...
Machines are only for secondary heroes to clear out minor creatures and mines.
