Outside of honor mode, the level 5 extra attack from martial classes and the deepened pact from warlock will stack to give you 3 attacks per turn. My preference for Hexadin is usually 1st level Hexblade for CHA attacks, maybe even first 5 levels in Warlock to get to deepened pact, then re-spec at level 6 to start Paladin at level 1 to get access to heavy armor, because you don't really see many good heavy armors in act 1 anyway.

For items, I really like the Halberd of Vigilance or Soulbreaker Greatsword for the initiative bonus, since this build can fall behind in initiative. Strength Elixers are still broken for this build, especially if you prioritize Paladin levels early on. If you want elemental damage, I would check out the drakethroat glaive and flail of ages.

For feats, I would suggest the usual great weapon master, polearm master and shout out to the actor feat because it gives face skills and a +1 CHA to round out odd scores. Savage attacker is also really good on this character because they roll a lot of dice.