Ok so lets break this down (as best I can on my phone
lol)
Good points:
Only 30 goblins
2 shamans for 30 goblins
No drum
For a goblin army of this points value there is a god if your only facing these numbers. This isn't much bigger than my kingdoms of men army and in some respects mines tougher. It will be easy to break them and once it rains it pours with goblins. Next, a second shaman? I just don't get it, one for fury fair play but there isn't enough goblins to warrant a second in my mind and you really can't rely on one for transfix at a 5+, your 45pts up here. Third there ain't a drum, in many ways the one of the most potent things for a moria player, so there ain't no rerolls or courageous goblins.
Bad points:
Double trolls
Healthy store of might
Durburz
Your biggest problem is a combination of the top two, the trolls backed by might means trolls where they want to be which equals a very upset Sharazad

you have two choices, shoot the captains or shoot the trolls. I would shoot the trolls as they will make sure you can't hurt the captains. For this stay manouverable, riders with bows should help with this, yes they will take flack from the goblins archers but from what you tell me there are only ten. One troll dead, the job is easier, two trolls dead, provided you play smart, and you have a waaaaaaaay better stance! Durburz isn't much of an obstacle but he can lay the hurt when he wants. I have had him wade through troops before despite his fight value and also has 3 might to boot. And an increased stand fast helps with a broken force so once you have the upper hand go for the jugular and butcher him, it will be the killing blow.
Of course all this is easier said than done
So what should you add?
Eomer on horse
At least four more riders
Royal guard on foot
And if you take theoden I would take him on foot with your main block. Your third hero I would make a captain with shield on foot too. There may not be as many goblins as there could be but with an added troll you will need the might where the fighting is thickest and Eomer has three for the riders.
So there's my opinion and if the person who has the goblins I mean no offense with my analysis of your army, it's just my view