Orcs. Upgrade or alternative upgrade?

Executioners don't impress me; they have less health than chieftains, and the -2 to morale against most enemies isn't effective.

In my opinion, executioners are chosen for their double attack, and certainly not for lowering enemy morale.

And the main defense of an Orc is rage points. Approaches to the Centaur are defended by traps.

I've played a lot, and I've always taken Centaurs geared towards melee combat, so that if they are reached, they can respond properly; maneuvering isn't serious. And traps don't always work. However, it's a matter of taste and preference, and I won't presume to say what is more advantageous.