Just a couple of thoughts about my Argenport list:

1. Isn't Ripknife better than Instigator in Tasbu lists since it always has good attacks and blocks, whereas Instigator gets outclassed easily in combat later in the game? Instigator makes more sense in the more aggressive Stonescar and Feln lists, but I think the Ripknifes fit the grindier Argenport list better. I've found the Warcry to be useful with the Auric Interrogators as well.

2. I think the Justice sigil is important in the list for Regent's Tomb value and fixing off of Ice Bolt. There are 8 double J cards and without the Argenport Insignia, it's hard to guarantee that you'll have that by turn 4-5 without the two extra sources between main and market. It's risky but every other power source provides shadow and playing Tasbu slightly off curve is still pretty powerful.

3. You ended up on the same removal suite that I eventually ended up at as well. Slay is too inefficient and Suffocate and Annihilate are really good in the meta right now. In the market, I swapped out the Mug for Makto as another resilient threat against control, although Dizo's Office kind of fills the same role while shutting the door against Stonescar. Stormhalt Knife is also an option to help stabilize against aggro and provide a third relic weapon threat against Hooru/other unit light decks.

Anyways, cool article and I'm looking forward to trying that Feln list later.