I agree with your choices, Jund and Broodbraid decks are the most consistant ones with the current coded cards, their only weakness lie in the starting hand and red mana sources, if AI doesn't get one immediatly, he's screwed.
Blade Delver is also very nice, but unfortunately Snapcaster Mage is more player deck oriented than AI because the latter doesn't know how to use it at all, and is code limited as non counter spells only.
As I am currently playing more in Standard, Block decks, I use Orion79 reference decks to compare with those I want to test, or I just grab a top block deck from tournament.
As for the "annoying deck that make you make a counter deck one", I have been struggling against those decks (which are available currently in the Playdeck brainstorming thread):
RTR Jace Nin : sometimes the AI is clueless, sometimes you can't do anything with AI miracle wiping the floor and countering everything. Staff of Nin is a big hassle because of sting and card bonuses, and Detention Sphere remove any tribal like thread. Now to learn the AI to not lose from decking and it will be a real pushover...
Lifebringers Deck : Good job Orion79, you made an annoying life deck that AI love to use. Racing damage is quite impossible and once Test of Endurance is in play it's game over.
Pure Evil : Wow, a non new coded card deck.
The equivalent of Explosion.dck but in UB, it heavily rely on Ashnod's Transmogrant and such cheap buff to pound really fast, and Immolation is here to stop thread early. In fact, I found that it's more consistant than Explosion since most of its buffs are permanent.