what about a Thopter Assembly

I feel that Thopter Assembly is a very very slow card. This deck has an average CMC of 1.8 and a high CMC of 3. As Thopter Assembly is a 6 drop card that offers little synergy while at the same time being inordinately difficult for this deck to cast I can not say that it would be a worthwhile addition to this decks board. This is a modern deck and as such streamlined to succeed against multiple strategies.

4 Abrupt Decay in the maindeck seems like a lot; have you considered maybe running only 2 or so and adding in a couple of Serum Visions? Also, Surgical Extraction is better than Extirpate in the sideboard.

What about Metallic Rebuke in some conjunction or in place of Stoic Rebuttal ? In modern if games are not going long (which often they do, sometimes they don't) being able to get the counter out earlier with improvise could be nice.

Metallic Rebuke is a card that I considered but ultimately went without as the current moderne environment is able to deal with Mana Leak-like countermagic with too much ease. We have no desire to stop most of the enemies casts, just those that disrupt us or threaten infine shenanigans.

I am aware that Surgical Extraction is generally better than Extirpate however my choice exists because of how meaningful extirpate can be versus the strategy that we would use it against. Namely living end and storm. It is poor form to mearly considered a single card as always better than another as with magic what's more important is what work best given the specific deck. For example mine leaves up tons of mana every turn as my win-condition is reactive not proactive so the cost for Extirpate is often 1 thopter or servo which is a well spent trade.

Finally the the number of abrupt decays in the main board is perfectly reasonable as virtually no deck that is modern competitive would not suffer sufficient loss to it.

Sorry, I just wanted to point out that some cards are ALWAYS better than others. For example, Hieroglyphic Illumination is strictly better than Inspiration because it does exactly the same thing except it has the cycling ability. While there are a number of situations where it is not correct to say that one card is strictly better, sometimes it is true.

I would recommend Serum Visions over Opt in a combo deck as Serum Visions digs 3 cards and Opt digs either 1 or 2 cards. Even Sleight of Hand would be better as you know both cards before you pick. I know Opt is instant speed, but your deck is mostly tap out anyway- you're not playing enough instant speed stuff you need to hold up to lose out on the power difference between Visions and Opt.

Also, to protect your combo, I like some amount of Spellskite and/or Spell Pierce.

Finally, if you can shell out for it, Ensnaring Bridge doesn't hurt your deck basically at all and just wins against certain decks.

I have answered why I feel that the choices made are best in the above post so please feel free to read it.

While serum visions and my choice of counter magic has been covered I have not denoted why I forewent Ensnaring Bridge. Simply put rawly will o have few enough cards in had to make its inclusion meaningful. Frankly bridge is a liability to a deck that regularly pumps out 2/2's and at times 3/3's. I cannot fathom as to why I would willingly obstruct the core of my deck in such a way. For this reason alone I run so many Abrupt Decay as the bridge can hinder the action potential of this deck.

cool deck!

Its a decent version of the deck, but i personally don't like it because it is a very complicated combo

I assume I'm correct in thinking Indomitable Creativity would be too inconsistent to bother running here, but I feel like you've got too many moving parts here. How do you deal with artifact hate or board bounce effects?