Three drop slot is really overloaded in that list. I think it should be in the deck, but I’m not sure if it’s maindeck or sideboard yet.

Try a bant shell splashing for CoCo and township. Also, I’ve been tuning a deck and 4 drogskol captain and 4 phantasmal image are insane together. Really good in racing.
These are the nonlands in my list.
4 path
4 birds
4 hierarchs
4 image
4 rattlechains
2 selfless spirit
3 bygone bishop
4 captain
4 spell queller
4 company

For utility lands i run 3 township instead of mutavaults. The mana base needs tweaking but the nonland cards seem great from my testing.

I’m also pleased as punch to hear that queller matches up favorably against fair decks, since jund and abzan are the matches I most worry about. obviously things like the swords granting protection, and mirran crusader exisitng (and new thalia being printed, which seems plausibly playable) make he matchups playable, but it’s nice to know that I can safely maindeck a few cards that give a distinct edge.

However, your argument about Vial is incorrect, both in reference to Merfolk and in reference to Spirits. Merfolk often leaves its Vials at 2, but that is neither correct in all instances nor necessary. Spirits plays the same way, as there are several 2 drop spirits that are both available and powerful to fill the 2 drop slot. Of those,

Rattlechains
Selfless Spirit
Anafenza, Kin-Tree Spirit

are likely the strongest, but the tribe also has access to

Spirit of the Labyrinth
Kataki, War’s Wage (and incidental shutdown of a faster aggro deck plays right into the aggro control shell UW Spirits Vial should be developing)
Spectral Rider
Keening Apparition/ Kami of Ancient Law if you find yourself needing a mainboard Disenchant

The deck may also want to step outside of its tribe and include Thalia, Guardian of Thraben to maximize its aggro/disruption package as another 2 drop.

In addition, if you buy into the argument for T3 cast Drogskol Captain, vial in Phantasmal Image in response to removal, you have yet another 2 drop to include. Testing with this strategy thus far has proven highly effective, as most decks cannot deal with a +2/+2 Hexproof board when you have access to Spell Queller to deal with Supreme Verdict and Spell Pierce for any other sweeper effect. Frankly, most decks cannot easily deal with a pair of 3/3 Hexproof fliers in a deck with access to countermagic, so the only option for non-linear-aggro decks is to race you, and you will win in this scenario. While this is something of a Magical Christmasland argument, it demonstrates that you can spend your first and second turns playing a vial and disrupting your opponent and still be just fine.

Re: Use of Vial. Aether Vial is a very strong card for spirits decks, as it negates countermagic, the non-sweeper removal type that Hexproof doesn’t touch. The greatest advantage Spirits has over Merfolk in this regard is that we don’t need any 4 drop creatures, so a game playing out with a Vial at 2 in tandem with, or simply with the ability to become, a Vial at 3 lets you cast any creature in your deck except for Mausoleum Wanderer.

Lingering Souls and related Spirits token generators don’t belong in a Vial deck. A more midrange-esque build, certainly, play souls. But then you still haven’t actually solved your problem. You make yourself all the more damned by sweep effects, and the presence of Engineered Explosives in many sideboards will ruin your day, making you a worse BW tokens. Now, if you settle on a midrange spirits build, you should be playing Jeskai spirits, not Esper, because Bolt is superior to any card black offers you in this shell, and 4 color decks still aren’t really viable.

In sum: Lingering Souls and related effects do not follow the game plan of a vial deck, and should not be included. If you want more than a minimal noncreature component in a Spirits deck, Jeskai is superior to Esper.

It’s pretty fragile and the three drop slot is a bit choked as is. You don’t really need it to clear the road for attackers since fliers aren’t too common in Modern and I think if you need to use it defensively then you’re in real trouble, this deck does not want to get involved in creature fights.

I’ve been looking at Spirits as a ‘damned if you do, damned if you don’t’ type tempo deck. It’s probably more like D&T than it is Merfolk, to be honest. The reason I say this is because of how many spirits play into this mindset. If you go t1 Mausoleum Wanderer, t2 Rattlechains (or Selfless Spirit), t3 leave up mana for Spell Queller, flashed in Drogskol Captain, Remand, etc. what is your opponent supposed to do? Cast a bolt to hit a guy? You can protect it with at least 8 creatures in your deck. Cast a sweeper? Selfless Spirit takes care of that. Cast their flurry of pump spells like in Infect or Suicide Zoo? Stop it with Vapor Snag or Path or even just counter it with Wanderer. Meanwhile you’re beating down for 4-6 a turn (since most combat happens on the ground in Modern).

This is why Selfless Spirit is perfect for the deck. It’s a clock. It protects you from sweepers (which I’ll get to why that’s so important), can help you win in stalled board states by chump blocking and then sac’ing to save your team and in a pinch, can be flashed in to protect some spot removal with Rattlechains.

The reason why it’s important to protect against sweepers is because the benefit of playing Spirits over any other tribe is the token makers. All of your guys are weak toughness. Mix that with token makers and you have a recipe for disaster when it comes to sweepers. Lingering Souls is a very solid card in Modern, especially to push you into the late game. Souls (and others like Midnight Haunting and Spectral Procession) are the reason Spirits can be a solid tribal deck. Mix those with Drogskol Captain and Phantasmal Image and you have a recipe for overwhelming your opponents quickly before they can recover.

Here’s my list:
http://www.mtggoldfish.com/deck/444033

That being said, my deck is a work in progress, but I think Lingering Souls (or potentially Midnight Haunting) has to be in the deck somewhere. It’s too powerful with Drogskol Captain. It’s even extremely powerful with Mausoleum Wanderer (which is Delver like in power).

Use with processors like wasteland strangler, blight herder etc.

This could be cool with processors. Like path their t2 play, then spell queller t3 play, then use the 4cmc processor eldrazi to counter t4 play

It’s interesting and I may have to finally reevaluate my opinion on Image if this deck ends up working well. I wasn’t very impressed with Selfless Spirit. With all the hexproof I didn’t really need the ability and a 2/1 flier isn’t good enough for Modern. How’s it worked for you?

It’s good enough that I’ve seriously considered adding it to Merfolk. I didn’t, but I thought about it. And trying to find non-tempo disadvantageous ways to take advantage of the ability. Haven’t found it yet.

Interaction*

Also, another great international is Spell Queller + Vapor Snag, using the first half of the trigger on the stack, returning it to your hand with vapor snag, permanently exiling the spell, then being able to recast it with Aether Vial.

Let me know what you think.

Azorius Spirits.dec, Built with Decked Builder
http://decks.deckedbuilder.com/d/217560

Surprisingly enough, my copy targets have been split 50-50 between Captain and Wanderer thus far. Part of it is a function of the decks I’ve had the opportunity to test against thus far (the counterspell clause was very relevant), but as it turns out, a T1 Wanderer –> T2 Image –> T3 Spectral Procession sequence was a fairly relevant clock.

And yeah, I’ve been thinking about Favorable Winds. I’ll definitely test that one next if I feel I don’t have enough pump. There’s a nice spot for it on my curve.

My problem with the tokens generators is that my experience with BW Tokens, both against them and playing the deck, is that it they’re really slow and you need quite a few Anthems to make the deck good. The current lists don’t have enough to really make things work. Favorable Winds might be the missing piece.

I’m still really down on Image, though hexproof is the reason to run the card. Do you copy Captain enough to make it worthwhile?

Not denying that it is quite narrow, but I think the versatility and better stats should make up for that and it will see a little more play than Sculler.

I’ve been looking at that Bant list for quite awhile and I don’t think it’s better than Abzan Company. When all the gears are meshing and it’s running as designed, yeah it’s remarkably powerful but I think the lack of the combo ends up costing the deck.