GGReload/Millia Rage/Strategy

General Tactics

Millia's gameplan revolves around pressuring the opponent and/or fishing for a hit that leads into a knockdown as she has a variety of ways to confuse and deceive the opponent thanks to her speed, frametraps, overheads, and especially her overwhelmingly powerful throw game. Her gatling options are limited though, and she has difficulty maintaining constant pressure, thus a Millia player must learn to maximise every given opportunity and squeeze every possible frame out of advantageous situations, in addition to learning to stay unpredictable in order to keep her rather basic tools effective. Her low overall health is another factor that makes it imperative that the player must learn to rushdown cautiously, choose their approach points with care, and always stay one step ahead of their opponent.

Neutral

Thanks to her almost unparalleled movement options, Millia usually holds the advantage in neutral. Your goal is to establish dominance and maintain control of the situation by playing a strong footsie game with the tools at your disposal, such as, again, your movement options including your two airdashes and Turbo Fall, 5P to preemptively check for (air)dashes and jumps, f.S to control the space directly in front of you, 2D to play footsies and whiff punish, j.P to control the close range air space or to catch the opponent carelessly hanging out in the air (do a dash jump with 669, chain j.P a couple of times, confirm into j.H), j.D to occupy the opponent's air space and fish for counter-hits, and the all-important pin, Silent Force. Aside from f.S, which requires you to be at a very close range or to have meter to be of any real use, all these tools are to be used to maximise every chance you get to score a knockdown or at least start pressuring your opponent. Despite her trademark being terrifying okizeme, Millia actually requires a very strong footsies game to be truly effective and her skill ceiling is quite high due to the amount of awareness required to convert properly off any given situation.

Offense

Not unlike her combo theory, Millia's pressure could be divided into a series of components that are to be mastered and used efficiently together in order to form a plan of approach. These components are her frametrap game, high/low game, and her all-important throw game.

Throws and frametraps

Thanks to her high speed, a common situation you'll find yourself in is dashing in on your opponent and getting them to block a 2K. This move is one of the cornerstones of her pressure and is +1 on block, allowing you to chain it a couple of times or stagger it and (or) dash up and throw. Once your opponent starts recognising your pattern of 2K>throw, you can instead gatling that, or those, 2K's into 2D, which will frametrap and catch jumpouts and conveniently net you a knockdown as well. Another common string is 2K>5K>2K, as 5K is jump cancellable.

Some other interesting frametraps are:

2K>2S>2H>2D

Useful to catch your opponent trying to mash or jump out of your 2K pressure, and has 2 jump cancellable points.

2P>6P>6H

If the 6P catches the opponent mashing it'll stagger them and allow 6H to combo, netting you a free Secret Garden setup.

Another extremely useful tool is her roll (236K). The usefulness of this move will decrease as your opponents' skill level increases, as it is easily punishable, so one must learn to use it sporadically and unpredictably. The roll has tons of high invul frames and will go under a huge number of moves, allowing for tricky approaches; another use for it is to cancel it from a normal to get your opponent to block momentarily so you can throw them. Again, the effectiveness of this tactic depends entirely on your opponent's ability to react accordingly and punish this approach, so you'll spend lots of time learning how to master this move. A poor usage of this tactic that is common among newbies is to gatling all the way into 5H xx roll, as they fail to recognise that their approach failed during the gatling and try to desperately try to get one last, very easily punishable mixup in.
Rolling becomes more effective the more the opponent is on the defensive and unsure of what to do, so get creative and learn to recognise and abuse their tendencies. One such tactic is to recognise that your opponent is sleeping and sneak a 6K in at further range, which is a rather unusual usage of this move; hit or block, it will probably disrupt your opponent's mental stack as it wasn't expecting an overhead at that range, thus it is the perfect moment to cancel the 6K into roll to get a throw in during the brief moment of confusion. Again, this is just an example of the myriad of applications the roll has; like many of Millia's tools, you'll spend lots of time learning how to master this move.

Turbofall (j.236K) is not dissimilar in application to the roll, except it involves Millia coming down from the air at an angle. As such, it is similar in application; do it raw to catch an unaware opponent and throw, cancel something into it then land and throw, abuse occasions of frame advantage to minimise the danger of retaliation such as after throwing your pin, turbofall then throw, etc...
An additional application though is that turbofall allows for tricky crossups that are a bit harder to react to compared to rolling, as it enjoys a recovery of only 8 frames. In these occasions, try going for a reset into a combo instead. It is still fairly reactable though, so it goes with the usual warnings.

This section could go on forever, but in the name of keeping things concise, it stands to be reiterated yet again that Millia's tools have an incalculable number of applications. Learn your frame data, abuse your plus frames, go for silly and unexpected stuff, c.S xx 214S into dash up throw, c.S TK turbofall crossup throw, c.S xx 214P FRC throw, IAD j.K>j.P land throw... Millia rewards creativity, experimentation and dedication.

High/low mixups

Millia has a few setups of this kind worth mentioning. Get your opponent to block a c.S (in the name of keeping things varied and letting your opponent know that throws aren't all you have, you could gatling into this from chained 2K's) then cancel it into TK Bad Moon (2369P, a.k.a. TKBM). This is a nigh unreactable overhead that nets you a knockdown, and works even better if you cancel it from the first hit of c.S, though harder to do.
Once your opponent catches on and blocks high or mashes, you have two options:

2S

This will beat both options, is jump cancellable allowing for more trickery (you're usually close enough for a TKBM to hit from there! And remember the jc empty Turbofall land throw talk from before?), and gatlings into 5H>2D.

214P

This is the ballsy one. Note that your opponent can beat both this and TKBM by airthrowing you. You're negative on block, but if you have meter to FRC then you're neutral on block instead and at range for another TKBM or a throw. The FRC point is what really ties this all together compared to 2S as it is sure to keep your opponent confused and scared.

You don't have to TKBM exclusively from c.S. Get your opponent to block low, possibly while keeping frame advantage, such as from, you guessed it, a 2K, then TKBM. It's risky but effective, and if you can learn how to FRC it you can at least minimise the punishment taken in case it gets blocked. Again, get creative, abuse plus frames, find places to sneak this 16f overhead at unexpected times, just like a throw.

Your other high option is 6K. This is not as versatile as TKBM, but it has its uses, and despite being a fair bit slower it'll still hit often if you're sneaky, and it's +3 on block which is actually pretty good. Usage of this normal is already mostly covered in the combos section. Nice to throw out every once in a while if your opponent is scared and standing still, and remember that it dodges lows for 20f.

Defense

Effective usage of your movement options, Instant Blocking, Faultless Defense, Dead Angle Attack, and your roll are going to be imperative to guarantee your survival, as Millia only possesses a subpar Overdrive reversal to count on as far as invincible defensive options go. Ultimately, Millia is as vulnerable herself to pressure and okizeme as she is excellent at applying it, so ideally your neutral game should be immaculate and as clean as possible in order to prevent being put into a disadvantageous situation.