This my build for a U/W spirits. Here's some info on why I have the current selection of cards

Aether Vial -- It took me a while, but I finally got around to purchasing 4 of these. Currently, I chose to  run all 4 in the deck. After running the deck fully built but without any Vials, I feel unsure if I like playing a turn 1 Vial over a Giver of Runes, or more importantly, a Wanderer. However they do help in the turns after, being able to drop a 1 and 2 cost creature, and so on.

Cavern of Souls -- Decided that running 2 of is my best bet.  I've seen many lists with only 1, but feel that leads to too much inconsistency. 

Horizon Canopy/Waterlogged Grove -- I decided to run on of each. These have Been pretty  useful especially mid-to-late game with the provided card draw. I really wish this deck had room for more card drawing.

Mutavault -- I feel very undecided about running these. Though they seem good, and have seen them played in many different tribal decks. However I feel this deck doesn't lack for creatures. If I were to run any it would have to be only 1 copy ,but I'm very hesitant to run at all. If I were to run a creature land, I would almost run a single Celestial Colonnade. 

Hanged Executioner -- I'm not sure why, but I really want to run these. First off, their ability to exile is more then extremely helpful. Secondly, with the addition of a spirit token, adds real synergy with Mausoleum Wanderer. The real downside is that the 3CMC slots for the deck are already quite full. Not to mention, I've found it difficult actually finding something I'm comfortable with cutting in order to fit these in. Sideboarding out Kira/Thalia for these is a strong possibility.

Distant Melody -- One of the biggest weaknesses of this deck is playing out your hand too quickly. Leaving any answers to top decking fairly early. I like to run at least one copy for that mid to late game boost, that usually is just what I need to win the game. Similar to how Bant Spirits play Collected Company. 

Spectral Sailor -- A great spirit, the card draw can be a real game changer to force the tempo to lean in my favor. However I dropped these in order to fit Giver of Runes and Aether Vial. Both of which, have more then pulled their weight over and over.

Saving Grasp -- Now here's a card I feel is underplayed in U/W colors. Though feeling unsure, I decided to run 2 copies, and was quite pleased with the result. Not only do they help save a spirit from exile, such as a single Drogskol Captain, they even allow a replay of a Rattlechains, providing a chance to give hexproof a second time around.  This card also pairs well with Spell Queller, allowing the dirty combo of being able to exile the targeted spell for good. Then the affordable flashback allows me to do it again. I don't play this card as much as I should.

Pure Intentions -- I specifically have these cards sleeved up for playing against a friend's discard deck. I make sure to put a playset of these in whenever we get together. I'm an ass, I know.

Azorius Charm -- Great tempo card in my opinion. Each of the 3 choices is an answer to different problems. I really want to run these more often.

1x Supreme Verdict - I decided to run this card after playing at my LGS and learning my local meta, which tends to lean creature heavy. Also I have found that this deck has an extremely poor matchup against elves, and this was an answer that found.

Thassa/Ephara -- have seen decks that's run 1 of either one of these, seem like they would be good game enders, if devotion was met. If not, both of the scry and card draw abilities would come in handy. Still unsure of where to make a cut of I wanted to play.

Kataki, War's Wage -- I have these for possible variance in my local meta. They pair when combo'd with Stony Silence, and when Aether Vials are sideboarded out.

Mindshrieker -- I found these while searching for different 2cmc drop creatures. Though their ability seems mediocre at best, i still have 2 sleeved up (the other 2 I put in my bird tribal). I haven't run main board yet, but think that it might be worth it

Tale's End -- Really like this card and am not exactly sure why. Stifle is obviously more Mana efficient. But since the release of War of the Spark, Planeswalkers have become alot more annoying and prevalent. And these are the best Anti-Planeswalker card out there, at least for blue.

Narset, Parter of Veils/Swans of Bryn Argoll/Spirit of the Labyrinth -- So this is kind of a weird set-up/pseudo-combo I came up with. I sleeved these up to add an alternative build to Spirits if I wanted a change of pace. And actually it worked out great. It allows me to run immortal Swans and remove the disadvantage of opponents getting to draw cards. 

Godhead of Awe - really liked the idea of running these, however casting cost is just to high. Would love to find a deck, or build a deck around these.

Windborn Muse -- love the Idea of building a pillow fort/tax Spirit deck. Have ran 2x of these in my sideboard many times and swapped them in for game two. The 4cmc is a bit of a pain, especially if I'm able to finally play mid to late game, and the 2 Mana tax per creature to attack isn't an issue for my opponent. *Shrug* guess it's just a pet card, and I can't help but like it.

Geist of Saint Traft -- ahh the Geist, what a great card. However the major disadvantage is it's lack of flying.  I used to swear by these, and still feel they're one of the best spirits printed.  Paired with Steel of the Godhead, that's game over.  

My opinion:

Overall there are 2 major weakness to the deck that stand out to me the most. First is card advantag and second life recovery. They're have been many games where I was forced into playing out my hand and being forced to top deck. It's not a great feeling. Especially against a deck that is drawing heavy, it's hard to keep having answers. It's at times I strongly wished I had the right answer to this. Dropping some spirits, and thus possible sacrifice tempo for card advantage?  My answer is still undecided.

I've considered running Remand, Ojutai's Command, even Kaya's Guile, just to name a few cards. Azorius Charm I believe is the most reasonable answer. Because it allows different avenues for a reasponse the problem that's presenting itself at the time.

Well that's my write up for Smells like Team Spirits. 

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