It definitely needs a lot of work.
As others have said, its far too good at low levels, being much better than the fighter. Especially at level one where it gets a Fighting Style AND a Leader Style AND a Commanding Presence. Most 5e classes have a single small choice at 1st level, not three.
It also gets three attacks, which is almost a signature ability of the fighter. That's a bad idea.
Okay, Tactician's Insight. Initially, this mechanic was balanced against the spellcasting of the eldritch knight, which is a 1/3rd spellcasting class (i.e. it gains more spellcasting every three levels opposed to a paladin or ranger that are half-casters and wizards or clerics that are full casters.
This class gets Tactician's Insight at 2nd level so it's a 1/2 caster now, and balancing against the paladin is the best baseline.
Right off the bat I can see it should get a third use at 3rd level, and a bigger bump at 5th level. In total it can use the power 20 times compared to a paladin's 15 spell slots. However, it doesn't improve, so it starts out pretty darn good and slowly falls away.
Most of the Commanding Presences are very much not 5e in design, and seem like direct copies of 4e mechanics. Getting half your Charisma or Wisdom modifier "to all defenses" from Insightful Presence for example. As you only have one defence in 5e (Armour Class) and getting a +2 bonus to it is pretty damn good.
And Inspiring Presence is basically regaining hit points continually (plus there's no combat limitation so its basically free hp at all times).
Having the level 20 capstone be a subclass feature is curious. I think only one other class does that. It's better to make the capstone iconic to the class as a whole than have to invent several high level abilities.
To get nitpicky, the language shows a very casual knowledge of 5e.
The Bravura Presence feature says:
When an ally who can see you uses an Action to make an Attack, the ally can choose to take advantage of this feature before the attack roll. If the ally chooses to do so and the attack hits, the ally can either make a Bonus Action to Attack or Dash after the initial attack. If the attack misses, the ally grants advantage to all enemies until the end of his or her next turn.
Right off the bat there's no flavour. Most powers begin with a small sentence that describes what's happening in the narrative/ world. But this is a small sub-power so we'll ignore that.
"Ally" and "enemy" are not a phrase the rules use Phrases like "friendly creature" are used instead. Also, 5e doesn't use "his or her" or "he or she". For most rules, the text uses the second person (you/ your). For other uses, the rules use "target" or "creature".
It's also not "an Action" it's "your action". Or "take" the "Attack action". It also doesn't need to be specified that the ally can take advantage of the feature: the phrase "can choose" covers that. The phrase "make a Bonus Action" is also awkward and not consistent with how the rules uses bonus actions.
The power would probably be:
Bravura Presence
When a friendly creature who can see you takes the Attack action, after the initial attack they can choose to make an attack or take the Dash action as a bonus action. However, if attack misses, attack rolls against the creature have advantage until the end of the creature's next turn.
Even this direct "translation" of the rules reveals the mechanic is a little unclear. If
which attack misses? The first or the bonus action attack? Given the bonus action is secondary, if they miss, why would they ever choose to use this power? And from a design perspective what kind of attacks? Should it be melee weapon attacks? Just weapon attacks?
It could be written to "makes an attack" but that opens up this power to use during reactions, which is problematic due to no firm rules on bonus actions being used off turns. Instead it could be "makes an attack on their turn", which would apply to both spell attacks and weapon attacks.
All this is problematic as
almost every feature in the document requires this level of editing/ revision.