First of all, the Lord doesn't need a plasma pistol. He's likely enough to kill himself from the sword, no need risking him with something else too.
I like what you're trying to do, and there's a good reason for it, but the problem is that your distractions really aren't very effective. All the anti-tank firepower in your opponent's army will go into your Rhinos, and the anti-infantry will go into the Chosen (who are mostly unsupported) and the Bikes. Quite frankly, they're not high-priority enough targets for me in general. 7 overpriced bikes, 7 chosen - not worried too much if they hit my lines. I'd rather deal with them than with 30 Berzerkers!
I would consider dropping the Chosen who you've made far too expensive, and taking a pair of Predators, Vindicators, Defilers, or Obliterators, or some combination thereof. That way, everything in the army moves 12", and there's a good amount of armored vehicles. In the same vein, I'd consider dropping the pp on the Champions (really the worst place they could be, if it overheats you lose a 66 point model!) and getting extra armor on the Rhinos (which are 5 points more than you have listed), it keeps them mobile. The Icon of Nurgle is a nice Icon, and functions well on already tough Bikers, but it's also expensive as heck, especially for a suicide squad that'll be rushing at the opponent to tie up firebases.