sultai controllo (Standard)

VS W/U Heroic
I feel this is a matchup you don't mind playing against as long as you understand how things go. Your best cards against W/U Heroic in game 1 are Thoughtseize, Bile Blight, Murderous Cut, and Crux of Fate. Their deck can come out very fast, but any card that interacts early with them and slows them down is excellent. Kiora is also very good against them, since most of the time they only have one threat to worry about. If they do have either a Gods Willing or Feat of Resistance to beat Kiora, they would have likely used it on your turn to counter your Kiora activation, which means you can then respond with a removal spell.
Out:
2 Garruk Apex Predator
1 Ugin the SpiritDragon
1 Temple of Mystery
2 DisdainfulStroke
1 Interpret the Signs
1 Dig Through Time
In:
2 Feed the Clan
2 Negate
1Pharika Cure
2 Tasigur the Golden Fang
1 Necropolis Fiend

I think Negate is strong in this matchup because they are likely to bring in Treasure Cruise and already have many targets in their deck anyway. Remember the long game will most likely favor you, and Feed the Clan is a card that can help you get there. It may look a bit strange to sideboard out a Temple of Mystery, but it's important that you up your density of spells against W/U Heroic. The mana curve of the deck is becoming greatly reduced in taking out the high end planewalkers. Having early black is crucial for casting the key spells in the matchup such as Pharika's Cure, Bile Blight, and Thoughtseize.

VS U/B Control
I think this is a matchup you're happy to see, but it's still far from easy. They have more counters than you, but other than that, things should be looking good. Game 1, you have some useless cards, but those can be thrown away with Sultai Charm. You want to time your Thoughtseizes so you typically don't want to automatically fire one off on turn 1. Sometimes it might be right (if you fear a Grindclock after sideboard, for example), but I have found that you're better off holding it to push through a key spell.
Out:
3 Bile Blight
2 Crux of Fate
2 Murderous Cut
1 Satyr Wayfinder
In:
2 Rakshasa Deathdealer
2 Negate
2 Tasigur the Golden Fang
1 Pearl Lake Ancient
1 Hero Downfall
Overloading on threats and the extra counterspells pushes this matchup further in your favor.

VS Abzan Midrange
Sometimes this feels like the mirror match since both decks play out somewhat similar. However, you have the more powerful cards and better card drawing, which makes me like this matchup quite a bit. In game 1, they will most likely be stuck with some poor cards like End Hostilities, Murderous Cut, and Bile Blight, and if they draw too many of them, they'll soon be shuffling up for the sideboarded games.
Out:
3 Bile Blight
2 Kiora the Crashing Wave
1 Sultai Charm
In:
2 Negate
1 Hero Downfall
2 Tasigur the Golden Fang
1 Silumgar the Drifting Death

You have the option to sideboard more here and bring in the Pearl Lake Ancient and the Silence the Believers, but you don't have too. It just depends on what you think they might bring in and how you think the match will progress.
As far as any of the aggressive matchups go, many of them have overlapping similarities. Abzan, Temur, and R/W Aggro all try to apply maximum pressure with their own respective element of disruption. Abzan has Thoughtsieze; Temur has counterspells like Disdainful Stroke, Temur Charm, and Stubborn Denial; and R/W Aggro has burn like Stoke the Flames and Lightning Strike. Your basic sideboard plan against all these strategies is to lower the overall casting cost of the deck. Keep in mind that planeswalkers like Ashiok and Kiora get much worse when you're on the draw. Therefore, swapping these out for other threats like Rakshasa Deathdealer is often times beneficial.
I feel that Sultai Control is a fun and exciting control deck in a format overrun by low-costed efficient creatures. If you're a control player at heart and you love rolling the dice with Satyr Wayfinder, then this might be the deck for you.