Well here is one of my latest lists. Haven't used this one before and I'm dying to get those freshly painted slayers on the battle field.

Lord Thorin Brightaxe- gromril armour, rune of stone, great weapon, master rune of spite 203

BSB Snorri Kugansson- gromril armour, rune of stone, rune of resistance, rune of cleaving 138

Runesmith Thror Fireforge- gromril armour, shield, rune of stone, great weapon, rune of spellbreaking 114

25 warriors- heavy armour, shields, full command 250
24 warriors- heavy armour, shields, full command 241
12 Thunderers- shields 180
12 Miners- prospector 156

18 Slayers- musician, standard, 1 giant slayer 231
23 Longbeards- full command 352
1 cannon- rune of forging 135

total- 2000
total dispell dice- 5

Its been my experience to go shooting or not going in between (with one cannon has never helped me enough). Of course that is my opinion I could be wrong.

Yeah, just 12 thunderers and one cannon isn't enough firepower if you want to include missiles as a part of your army. Otherwise, get rid of them and take all melee units. Also, that army needs some rare units! Flame cannons can be pretty awesome, and though I've never seen an organ gun in battle they appear to be good. If any veteran dwarves disagree, please so say, but I think the gyrocopters suck. When they crash they're ok, but its a totally random direction and you can't depend on it.

If you cna spare the points for 5 points more you can exchange the gromril armour and rune of stone for light armour and m.rune of gromril

Commenting on a previous post I use the gyrocopter to prevent march moves in my opponents army so that it gives me more time to either shoot or position my melee troops into a more favourable position. You could use it to shoot war machine crew with its template weapon (hits anything fully under it automatically-no randomising.) Never throw it into combat. The gyrocopter does need to be used carefully but stick with it, it can be a battle winner.