Disciple of the Pike Cavalier can do more than just whack $#!+ with a stick via their Tactician ability... handing out teamwork feats to the party is something.
Arcane Duelist Bard with a Longspear/Banner of Ancient Kings, and Flagbearer. Now we're talking about doing WAY more than just whacking $#!+ with a stick!
Being a proactive defender probavly means Combat Reflexes and Bodyguard. Order of the Dragon's Aid Allies would boost the bonus you give your allies' AC with Bodyguard. Disciple of the Pike Cavalier gets Weapon Training, and thus qualifies for Cut/Smash From the Air... legit AF with a reach weapon. Using a reach weapon means you probably want Weapon Focus and Weapon Trick, so you can choose to ignore said reach feature when the situation calls for it. Power Attack is required for Cut/Smash From the Air, so you might as well grab Improved Bullrush... this opens up additonal uses of Weapon Trick, and allows you to take Rhino Charge. Rhino Charge breaks action economy, which is as rare as it is awesome. And, charging shenanigans like Rhino Charge, go well the Pike's Charge class feature.
That's, like, nine feats... not including other stuff like Chain Challenge and Iron Will. You only get three bonus feats, so prioritize! Lol.
Sohei cMonk gets Weapon Training, and can Flurry with anything they have Weapon Training in... polearms are an option they can select. Flurry with a Lance from the back of your Monastic Mount. Lol.
You could take three levels of Phalanx Soldier Fighter, wear a buckler and wield your polearm/spear in one hand... then be a Swashbuckler, with reach. Lol.
Warrior Poet Samurai can use Weapon Finesse with the Glaive, and a Human could start with Weapon Focus and Bladed Brush... then be a Swashbuckler, with reach. Lol.
You could take one level of Warrior Poet, grab the Kitsune's Mystique flourish for Improved Feint, and go into Snakebite Striker Brawler for some fun Feint shenanigans.