As I've said in other posts, don't make Orcs stupid and muscled beings. Don't make them "Hulk Smash" please.
I think about Orcs and I would like to see a proud warrior race like Spartans from Ancient Greek, I also see people hardened by the dangerous environment, so:
ORCS STRENGTHS
-High natality: They reproduce fast, and it's common they gaving birth to 3 or more childs.
-Natural selection: Trained since birth to survive, the law of the jungle, only the strongest survive, that's why their race becomes stronger over the years.
-Military intellect: Being strong isn't useful and isn't enough if you can't think. There are several types of intelligence, kinetic, logic, artistic, etc. Orcs intelligence can shine during battles. Spartans were excellent war strategists.
-High pain threshold: Bodies hardened by the dangerous environments, they can resist more pain than other races and it's harder to wound them.
-Excellent warriors: Trained since birth to fight, they can handle all weapons in an excellent way, but their skills shine in close combat due to their superior strength.
-Connection with nature: They can respect nature in their own way, they don't hesitate in killing animals or use natural resources, but they only use them if they need them, they have to use every part of the animals and resources, they aren't allowed to waste nothing or they can be punished. They are expert in survival, remember? Here was born the bone carving mastery. And this is the reason why all their architecture looks primitive like leather, fur, bones, tusks,
ORCS WEAKNESSES
-Pride: They take pride in Battle. Their pride often can lead them to fight battles without reason. Wars cost resources.
-High mortality: Due to their training, pride and hard environment, the weak die fast.
-Military focus: Being the military force their main focus, they can lack of knowledge and experience in other areas, like technology for example. This can be solved in a way by asking help to their allied races, like infernal Demons, Undead and Boargen.
-Weak diplomacy: This can be slowly changed by Innammar, but ancient manners are difficult to change.
-Difficulty for magic: Due to their training focusing mostly on physical battle, and also "weaker" Orcs dying young, a minority of Orcs with aptitude for Magic survive, and due to the lack of experience in that matter, few Orcs can reach their full potential if they remain in Orcish lands. Those who want to learn and train magic, leave, that's why we can see just few Mages, Witches, etc in Orcish cities and towns, most of them are spread over the world. Difficult, not IMPOSSIBLE.
Thanks for reading, hope it can help to build Orcs in a different but not so different way.
Sorry Wolfy but even with google translate I was unable to read your comment.
About Orcs being good strategists I can totally agree, I absolutely got the image of "300" while reading this.
Natural selection sounds very "Orcish" as well, they need only the strongest Orcs, so natural selection is the best way for the Orcs to achieve that.
Being so close to the nature "Soil", means you respect everything created by it, yes you kill to survive, but you kill with respect and honor, and you take only what is necessary for you to survive, nothing more, nothing less.