For my table, I use the following version of the Banneret/PDK:
Rallying Cry:
At 3rd level, as a bonus action, you can choose a number of creatures within 60 feet of you up to your Charisma modifier (minimum 1). Each one regains hit points equal to your 1d10 + your Charisma modifier, provided that the creature can see or hear you. You can use this ability a number of times equal to your proficiency modifier. You regain these uses after you finish a long rest, though you can also regain a use by expending a use of your Second Wind.
Royal Envoy:
At 3rd level, you gain proficiency in the Persuasion skill. If you are already proficient in it, you gain proficiency in one of the following skills of your choice: Animal Handling, Insight, Intimidation, or Performance. Your proficiency bonus is doubled for any ability check you make that uses Persuasion. You receive this benefit regardless of the skill proficiency you gain from this feature.
Inspiring Surge:
Starting at 7th level, when you use your Action Surge feature, you can choose one creature within 60 feet of you that is allied with you. That creature can make one melee or ranged weapon attack or cast a cantrip, provided that it can see or hear you. That creature gains a bonus on the attack rolls and to damage equal to your Charisma modifier.
Bulwark:
Beginning at 10th level, when you decide to use Indomitable to reroll a saving throw and you aren't incapacitated, you can choose one ally within 60 feet of you that also failed its saving throw against the same effect. If that creature can see or hear you, it can reroll its saving throw and must use the new roll.
Leadership:
Beginning at 15th level, as an action, your mere presence can inspires nearby creatures of your choice. Whenever a creature within 30 feet of you makes an attack roll or a saving throw, it can roll a d4 and add the number rolled to the attack roll or saving throw. This effect lasts up to 1 minute, and ends if you are incapacitated. Once you use this ability you must finish a short or long rest in order to use it again.
Every Ready:
Beginning at 18th level, you regain one use of Rallying Cry whenever you roll initiative. Additionally, you can select two creatures when you use your Inspiring Surge, rather than one.
The idea behind the changes is to put it a bit more in line with the samurai for it's 3rd level features, given that Indomitable is likely to change in the new version of the fighter, I'll likely tweak Bulwark a bit once it goes live.
Personally I voted for Cavalier, but I actually would prefer to see an updated version of the PDK as the 4th option for the new PHB.