Skills and Super Ability of the Orcs.

I basically agree with everything, but regarding logistics... I don't understand what its usefulness is for Orcs.

Well, firstly: I generally think this skill is very useful and I take it for almost everyone.
Secondly: Orcs are a creeping race whose effectiveness doesn't depend on external factors (amount of mana per battle, etc.), i.e., they kill as much as they can run around in one turn. Logistics, combined with Warpath, allows them to make many more attacks in one turn (especially for machine gunners; you practically need to take Tilseck before the attack. Unless you're going up against heavily armored units right away).
Thirdly: Movement speed and, as an option, forcing a final attack at a moment that is advantageous to you.
Fourthly: Getting +4 to speed during a siege is also a big advantage, because storming a castle is one of the problems for Orcs.