These are the differences in my build:
-3 Doom Divers
+1 Lobber Crew (3x)
+2 Grimgor (2x)
+2 Urguck (2x)
-3 Armory (0x)
+2 Grimgor's camp (2x)
-1 Rip Dere Heads Off! (2x)
-3 Favor of Mork (0x)
-1 Waaagh! (2x)
-3 Smash-Go-Boom (0x)
+3 Seduced By Darkness (3x)
+2 Pilgrimage (2x)
+1 Pillage (1x)
+1 Troll Vomit (1x)
Stuff I didn't play:
Doom Divers - maybe a one-of, but you don't want to see it early.
Armory - Grimgor's camp gives you an Orc icon, can give you a bonus hammer (effectively) on the first two turns, and allows you to play developments to Quest for Pilgrimage. Armory is one cheaper, but you can't play Armory + Contested Village first turn, since they are both limited, and you can play Crooked Teef Goblin with either support card. And, with Grimgor's Camp, there is always the possibility of the ridiculous Camp + We'z Bigga + Squig-Herder opening.
Favor of Mork - Not horrible, but it generally ended up as a development when I played it. I like to play riskier cards in the last few slots, so that when they don't end up as developments, they do something big.
Smash-Go-Boom - would be WELL worth it if you could play it on opponent's turn in response to Verena. It is definitely a "risky" card, and I've had a single copy in at times. Would definitely play one if I didn't have Grimgor/RDHO.
Stuff I played:
Urguck - is easy to turn on with We'z Bigga and Followers of Mork.
Seduced By Darkness - The Empire version costs one and isn't as good; since Orcs can actually use it as a rush card, it's substantially better.
Pilgrimage - Bouncing a guy for one or two resources is way unfair. Generally best for bypassing pesky defenders, but you can play it after attackers are declared to create a mismatch, or to randomly mess with opponent's kingdom/quest.
Rip Dere Heads Off! - I'm not sure how much I like this card now. Not being able to use this to activate Grimgor's text makes it a bit weaker. It's best use is probably still flipping Grimgor to soak up an incoming attack; I just can't decide if that is enough to play 2 of each.