IMO, limiting the number of Trolls at the start to 100 (or less?) would be a good option. They'll take the minimum number of Consultants, and Dirty will take them as Butterflies (and Dirty doesn't need to be banned). For example, I can't take a Tier 2 unit anymore without some other meat. And 180 Trolls is just a huge resource drain.
Also, if you don't keep an eye on them, they'll be fired by turn 111, and then you'll be stuck... :D

And Goshu – yes, he needs to be banned.
In the last game, my Necromancer, playing as Castle, managed to get Nimbus to 130 skeletons from a single hero by turn 117, and without any artifacts. Tant arrived 10th, but I didn't need him anymore. Let's get Nimbus into the masses! :rolleyes: