While there's something to be said for a tide of Boyz, I agree... this isn't going to work. A single Predator Destructor will reap a truly absurd total against your army, and won't get so much as a scratch in return in all likelihood. The simple solution is to can the nobz as a unit, and distribute 'em through your squads. Give 'em klaws. Normally, I don't advocate using power fists specifically for going tank hunting, but honestly, you've got enough boyz that you'll get there. Besides, you need something to crack open power armour in close combat besides volume of dice.
I'd also strongly suggest distributing big shootas through the squads, and perhaps since you'll save a TON of points dropping the Nobz as a squad, you might have enough points to bring a zzap! gun or two. Not ideal, but it's something, and a zzap! gun can jack up armour pretty well when you roll decently.
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