I agree with G-RAm on everything he said.
Get a BSB. That will help alot.
You need some supporting units. Artillery if you want shooting, chariots or giants if you simply want to cause more casualties, wolf or spider riders in units of 15 strong if you want to disrupt your opponnent with a flank charge. Or you can take goblins with Fanatics if you simply want to be anoying (to both yourself and your opponent).
Or you simply take a large unit of trolls and keep it near both your BSP and general to both have a unit that can disrupt and cause casualties.
PLAYS: Daemons, Tomb Kings, Beastmen, Chaos Warriors, High Elves, Wood Elves (fantasy), Imperial Guard, Adeptus Titanicus (Epic), Eldar, Craftworld Eldar (BFG).