Armour is a great option to anti-air... if you're Kung Lao, Kenshi, tremor, Johnny etc. and get a full 30% combo from it. If you're say Liu Kang, your armour whiffs on jump ins and when it connects you get a whopping like 12%? Into a tech rollable knockdown.
My point is people say that characters like Jaqcui have good anti -airs; and to some extent they do. Up rocket is great if you read the jump in (except against Kitana because her jump arc is really weird for some reason) but not so good on reaction. 4u4 is good at anti-airing the reckless jump ins from half screen, but anything spaced properly is definitely a challenge. s1 is good for crossups, except it loses to all the good jump ins and almost all jump kicks. d2 is ok, but the good jump ins still beat it. This is a character that's meant to have good anti-airs.
I just wanna be able to play high tech and anti-air somewhat consistently. Give my d3 and extended upwards hitbox like ermacs; voila consistent anti-air! Or extended her jab hitbox up more, or remove the leg hurtbox on 4u4, or make d4 faster and increase the upward hitbox or extended the d1 hitbox much more vertically; there's literally heaps of options you could take to give Jacqui the same sort of anti-airs that Ermac and alien have without resorting to making all characters have the same generic boring anti-air. Playing high tech, Jaqcui already has to contend neutral with characters with ridiculous footsie normals, great pokes and good footsie range; it just sucks even more when characters get to jump in or over you basically for free because if you want to risk anti-airing them, you're gonna be eating a full combo.
Also the discussion saying jump kicks shouldn't be considered when talking about anti-airs I disagree with. Quite a few character set conversions of jump kicks Midscreen and almost all get conversions in the corner. If you're gonna make jump kicks that strong on hit, you have to make them anti-airable.
EDIT:
You also didn't mention, but D'Vorah has very good anti-airs as well with her jab (I think it's s1?) and her d2 that honestly would be on par with mileena roll except it doesn't grant full combo.