Matchups: 

MonoWhite or Zombies (they are different on site but actually the same in games): Very favorable. 

Remove all their creatures/threats and they usually will run out of gus much earlier than you. Their attempts to disrupt your hands usually doesnt matter and most of their cards is basically dead (Hole. Skyclave, Kathar)

• Out: 1 Divide by Zero, 2 Geistflame Reservoir (but if they dont play Skyclave Apparation you can leave them in - its great to deal with creatures) or 1 Memory Deluge
• In: 1 Frost Bite. 1 Cinderclasm, 1 Crush the weak and 1 Solve the Equation.

UR Delver \ Grixis Delver \ UB Delver: Favorable

A lot of small threats and few ways to protect them. Remember about Saw it Coming and try to stall the game. You win the game of resourses since you have a lot flashback draw a card effects. Geistflame Reservoir is your best card here.

• Out: 1 Solve the Equation, 1 Serpentine Curve (you can expect Test of Talents from enemy, so removing one of this doesnt hurt), 2 Draconic Interbention,  1 Seize the Storm
• In: 2 Malevolent Hermit, 1 Frost Bite, 1 Test of Talents, 1 Divide by Zero (or if opponent playing Witches - better side in Cinderclasm or Crush the weak)

UR Dragons or Turns: Even

Depends on how fast you can put Serpent that are 7/7 or 10/10 and combo your opponent. Some dead cards in main deck from both sides. Remember about Goldspan Dragons and keep some removals for them. Also: Geistflame Reservoir is your best card here.

• Out: 2 Draconic Intervention, 1 Cinderclasm, 1 Solve the Equation, 1 Serpentine Curve
• In: 2 Malevolent Hermit, 2 Distainful Stroke, 1 Test of Talents (for their turns or counter magic)

MonoGreen: Less Favorable \ Even.

All depends on how much Ranger Class and Snakeskin Veils they pull of. Also Blizzard Brawl is not so dead card that seems on first place. Set a prior to slow down Cards Advantage from opponent and searching Draconic Intervention. Usually, if you able to stabilize its a win. Just remember about creature-lands.

• Out: 1 Solve the Equation, 1 Memory Deluge, 1 Kazuul's Fury or another Memory Deluge 
• In: 1 Cinderclasm, 1 Crush the Weak, 1 Frost Bite, 1 Divide by Zero (if they playing Toski, otherwise you can ignore this option)