Just a heads up, that you don't need to take the Megaskull Staff if your Weirdnob Shaman isn't the general, so I wouldn't bother taking that as one of your artefacts. I would give him the Shamanic Skullcape for better casting. Also, the choppas warclan forces your general trait to be Checked Out, so your Maw Krusha Megaboss will have to take that +2LD aura choppa specific command trait. Also, I think you forgot to include the extra one you get from taking a battalion. I would highly recommend giving the Megaboss on Maw Krusha the Ethereal Amulet since it gives him signficantly higher survivability against a lot of weapons and makes him hard to shift if you use the All Out Defense (re-roll ones to save in CC) command ability.
I would also give one of your warchanters Get Em Beat rather than both having Fixin Beat since you can only cast one each a turn anyways, so you're missing out by taking two of the same. It's also very useful if you use it on any teleported units before they are sent there since they can charge 3D6 (which for ardboyz, with the +3 to charge with the drummer and likely rerolls from choppas means almost guaranteed backline engagements). I would also consider consider splitting the two 15 man ardboyz squads to 3 units of 10 Ardboyz to give you more board control, or even taking another brute squad and using the extra 40 points to take the Balewind Vortex for your Weirdnob Shaman. Also, for such a big unit of Gore Gruntas, you'll want the Jagged Gore-hackas for the extra reach, since it's unlikely you'll have the entire unit in range with only 1" weapons for Pig-Iron Choppas.