Let's talk Azir: Why his kit is a problem and how a possible fix could look like
Let's start off by saying that this post is NOT about Azir needing buffs. No buffs to Azir should happen until he gets changed in a way that make his kit less problematic.
Azir has a big problem and it's time to face it: His kit is impossible to balance for both proplay and SoloQ play. If he's moderately strong in the LCS he'll still be weak in SoloQ but if he's moderately strong in SoloQ he's pick or ban in proplay. Why is that?
But what is the actual problem with him that makes him so hard or even impossible to balance properly?
The answer is simple: It's his kit.
He currently holds a fairly powerful poking tool on his Q ("Conquering Sands"), his Sand Soldiers deal a lot of sustained damage once he hits 4-5 completed items, his E ("Shifting Sands") is a mobility spell that can save him from a gank OR can be used by a skilled Azir player to engage on the enemy in combination with his AoE knockback ultimate ("Emperor's Divide").
Azir either has too much damage for the tools he gets in his kit or too many tools to justify the amount of damage he deals.
Let's compare Azir to the champion with the most similar kit: Orianna
Both of those champions command an entity (Sand Soldiers for Azir, the Ball for Orianna), both of them have a tool to move said entity. Both champions have to take positioning very seriously if they want to maximize damage output and minimize damage taken.
Yet Orianna is considered (by a lot of players) as having a balanced kit. Why? Because Orianna pays for her damage by having less mobility. It's a weakness she's been given for having AoE abilities both with decent damage as well as good CC.
Azir on the other hand lacks such a weakness. If he has bad positioning or gets ganked he can use 'Shifting Sands' and 'Conquering Sands' to disengage without suffering too much. And then there's still his ultimate that he can use to peel for himself. If you put Orianna into a similar position then her chances of survival are drastically lower because the only tool she can use to escape such a situation is her W ('Command: Dissonance') for the speedboost she gains from it.
It's save to say that Orianna could be taken as the norm for power budgets for any kits similar to hers. Azirs power budget in a sense tops hers astronomically. He has higher DPS than her, better mobility than her and an ultimate he can use to peel for himself or a teammate.
But enough with the comparisons. What could be a possible fix?
This is a hot topic for Azir mains because there actually are 2 different (common) playstyles for him.
1.) The Shurima Shuffle Azir: Like the title suggests the players using this playstyle want to be aggressive, they want to take the initiative. If they see an opening for a Shuffle they'll go for it and "insec" the entire enemy team (or parts of it) into an unfavorable position. 2.) The Emperor Azir: This playstyle focuses on high DPS, offensive but supportive play. Those players rarely go for a shuffle. They'll use 'Emperor's Divide' to peel for teammates that get jumped by the enemy frontline/assassin or to create a small window of time for his team to disengage from a fight.
What can possibly be done to appease both of these factions while fixing the problems his kit causes?
To make it even possible to balance Azir he needs an ability update on his E ('Shifting Sands'). There's a lot of possible fixes to it but the one that comes up the most is removing his mobility. This makes him more vulnerable to ganks or missplays, it opens up windows to punish him.
He then needs a different ability. Azir is the Emperor of Shurima. What would a soldier do if his Emperor gets attacked in a battle? He'd jump in to protect his lord. So his new 'Shifting Sands' could be another Soldier movement ability.
Once it is cast the soldier switches from an offensive to a defensive soldier with a short duration. He'll let go of his spear, equip a shield and rush in to protect Azir. This change is permanent for the affected soldiers, they will not be able to attack any more and can't be moved by 'Conquering Sands'.
It should still grant Azir a shield like it does right now but ONLY if the Sand Soldier can get to his emperor without passing through enemy champions. If the Soldier passes through an enemy champion the enemy will be shoved to the side rendering them immobile for a very short duration (e.g. 0.25s) but taking no damage.
This first part explains a possible ability change, but what about the Shuffle? Right now there's nothing hinting at keeping it.
There's actually 2 possibilities. Both will be explained in the following paragraphs:
1.) The Shifting Sands Shuffle: Loosely based on the current Shurima Shuffle, the Shifting Sands Shuffle would work similar to the shove explained above. Once Azir uses the new 'Shifting Sands' ability and activates the ultimate 'Emperor's Divide' WHILE the Sand Soldiers rush towards Azir the ultimate will form not behind Azir himself but in a line with the last summoned Sand Soldier rushing towards him.
If this combo is not used the ultimate will stay as it is currently, starting from behind Azir moving into the direction of the cursor.
2.) The Emperor Shuffle: Azir can not use his ultimate like he can do it currently. Instead it works similar to the first possibility but on both 'Conquering Sands' and 'Shifting Sands'.
Both of those would add skill expression to Azir.
To make everything feel smoother Azir would need a buff to his 'Conquering Sands' range. It currently sits at a range of 720 (it was nerfed from 875 prior to patch 7.19). An increase of 35-40 could be reasonable but it'd need testing. This would require a compensation nerf to his soldiers which could either be achieved by reducing their duration under tower OR them gaining an HP bar when under an enemy tower.
This compensation nerf should ensure that Azir can't poke people under their own tower without counterplay to his soldiers. (Tower attack range is 775 units. the new Q range would be 755-760 units, easily enough to poke and get out of tower range before it fires a shot).
Naturally this is just one of many ideas. If anybody has a different idea on how to fix Azirs problems or a rework idea feel free to comment them below. Work on Azir is slowed right now, so a pool of ideas could be the spark someone at Riot needs.
or
giving him SOME level of safety without giving him mobility on top.
Upgrade!, or as a cancel of whatever ability was used last (Conquering/Shifting Sands)? The first concern also applies to Shifting Sands. Which soldier will return to Azir? Requiring him to target a soldier for these abilities sounds very muddling and a huge skill barrier, even more than current Azir. This is the biggest problem that would need to be solved.