Bravado
You method of thievery is much more bold and brass than other methods, you prefer to attempt your ploys head-on. At 3rd level you've learned to put on a confident front genuine or otherwise. As a Bonus Action on your turn you can perform an act of Bravado, a shout or confident display. Choose two from the following Bravado choices these cannot be changed later.
Snap Out of it: You shake your allies to their senses within 10 ft of you. If they would be suffering from any ranks of Charmed or Frightened they can reduce the number of Ranks by 1.
Onwards to Victory: You inspire others to greatness. If you attacked this round, allies within 15 ft of you gain a 1d4 Bonus to their attack rolls if they target the same creature as you.
Swiftly my Friend: You may choose one allied creature within 10 ft of you, that creature may move up to half of its movement speed using its reaction.
Steel Thyself: You may choose one allied creature within 15 ft of you that creature gains a 1d4 bonus to a Saving Throw of your choice until the end of their next turn.
Fancy Footwork
Your confidence has some merit behind it. Your maneuvering in combat allows you to position yourself masterfully. At 7th level when you take the attack action your can perform one of the following maneuvers immediately afterwards as a Free action.
Spinning Step: You move 5ft which does not count against your movement for the turn and does not provoke attacks of opportunity.
Observing Dance: You focus your gaze on the target as you move gracefully. If it is the target of your Thieves Mark your Focus Rank on them is increased by 1 if possible. If they are not the target of your Thieves Mark they immediately become so and you gain 1 Focus Rank on them.
Steadied Stance: You gain 5 DR against B/P/S damage until the end of your next turn.
En Garde
You give your enemy the courtesy of a warning before you attempt to pierce through their defenses. At 10th level when you attack the focus of your Thieves Mark you can choose to drop all ranks of focus on them when you make an attack roll. If you do so the attack roll gains a bonus to its Crit Range equal to the amount of ranks dropped and on a successful hit it deals an extra die of damage for each rank dropped.
Mastery of Movement
Your focus on tricky movements across a battlefield has given you an edge at surviving and thriving in combat. At 14th level choose an additional 'Advanced Preparations' feature to gain. Additionally when you use your 'Stolen Move' feature you gain both a Bonus and Movement action.
Coordinated Bravado
Allies and friends are moved by your words and deeds. At 17th level once per Short Rest, using a Full Action your allies within 60ft of you can move up to their movement speed and make a single weapon attack as a Free Action.