Just spitballing another idea here, since it came into my head on a drive home from work.
So Jago’s fireball in instinct enables him to throw two of them at the same speed, but what if you could throw the second fireball at a much different speed?
All you need to do is press a different strength on the second fireball, if you don’t press one, the speed doesn’t change.
Thoughts?
So a fulgore fireball? Nah. It would throw off the balance a bit.
Good idea there but no thanks. I’m going to have to pass up on that suggestion too
How so? Explain, this is just in instinct
Because Jago’s double fireballs are already more difficult to get around without meter, AND they give him health regeneration, on top of the +2 frame advantage on every move. Adding the ability for him to choose varying speed for his fireballs on top of that to make him even harder to approach with or without meter would throw off the balance a bit, especially since he can build instinct super quickly if he uses Around the World.
Plus, it gives him one of the few tools he doesn’t already have that make Fulgore unique. With the amount of instinct a proper Jago player can get in a match, it’d be basically the same as giving him an ability that Fulgore has to sacrifice meter for, while he would get it guaranteed basically for free (possibly multiple times) over the course of a match.
Jago’s already one of the most powerful characters in the cast, he doesn’t need more.
That’s fair Fwufkins. I see, so if he had that ability, take away something in return. Reduce the amount of instinct he gets from doing around the world and reduce how much life he gets from an attacking fireball.
I forgot to mention that obviously you need something to take away to balance out.
Or since Jago is balanced as is, we let Fulgore keep the ability all to himself and worry about characters that actually need buffs/nerfs? 
Hey, I’m just spit balling here. Let a guy think 
Well, It is hinted that something will be done to his Fireball. What do you guys think it might be?
Angled fireball like Juri/Gouken? SADIRA BEWARE 
OMG IG MAKE IT HAPPEN LOL. Sadiras will plague Jago no more!
Hmm, he has been training his endokuken, so that would mean there has to be a significant difference from this season.
I don’t want him to get angled endokukens because it wouldn’t look quite right. I actually would like him to have an aerial endokuken just like Shago will. Also instead of the endokuken dropping an opponent when it comes in contact, it should force a stagger. This would show how his meditation has made his endokukens stable enough to allow him to have control over them. A knockdown makes Jago have to work for his resets/combos. This would make him similar to Maya where he can use them in sequence with a combo.
His shadow endokukens now travel faster and sllightly do more damage (they do knockdown though) and if Jago has 2 stocks of meter saved up, he can spend it all to get a massive unblockable endokuken (can be jumped over) that deals a large amount of potential damage.
This would make most sense to me what they plan on doing with the fireball. Ago will be able to charge his fireballs to make them travel faster. The catch here maybe is that if its charged all the way, it will a guard crush like attack in which Jago can rush in for the attack. Also with what the hint said, I’m assuming instead of that guard crush idea, a charged fireball that hits will heal jago outside of instinct, and more during instinct.
This charge is similar to how Fulogre can charge his cyber dash attack, in which holding it longer will grant greater distance and block stun. I assume charging the fireball will create more block stun as well.
This would make sense, since outside of Instinct, the fireball is not unique compared to other fireballs thrown by characters. Fulgore can cancel, Spinal can sort of rapid fire (for KI projectiles) and drain resources, Maya’s projectiles can gain unique properties on block and ARIA has full screen range instantly. Personally, the only thing I found about JAgo that is lacking, and already he is a strong character, is the fireball, which is only really used in Instinct to heal.
That’s like using Fulgore’s ability but less fireballs.