I'll give you Whirlwind Attack, but the other feats don't buy much for the polearm wielder in particular.Yeah, nevermind Combat Reflexes or Improved Trip or Spring Attack & WWA....
Combat Reflexes - Allows you more flexibility in fighting defensively. Nothing that benefits polearms in particular. Did you include it because it's a prereq for all the other feats you mention, or is there some other nuance I'm missing?
Improved Trip - The best part of this feat is not provoking AOO when attempting a trip, but it's specifically "while you are unarmed". Also, having reach means you can make melee attacks outside the reach of most Medium creatures, obviating the need to be able to attempt trips AOO-free. Attempting to trip a creature with a natural reach > 5' (Large or larger) is probably not a good idea considering the penalties.
Spring Attack - The feat that enables 5E style movement before and after an attack. Having reach means you can make melee attacks outside the reach of most Medium creatures, obviating the need to have a way of attacking them and ending your turn outside their reach.
What am I missing about these feats?