An interesting PP choice for Bladesingers is the Traveler's Harlequin. Multiclassing becomes completely open, bonus MC feat, situational double rolls, an actual encounter power (can reserve Maneuver if you wish though), and a L19 Daily or lower from any class you are a member of. A typical Eladrin Bladesinger will probably want MC Fighter (Deft Blade, Surprising Charge, the feats that add your shield bonus to Fort/Will) and MC Swordmage (Eladrin Swordmage Advance for an extra MBA 1/enc). Personally, it's my favorite, but the Neverwinter PP is good too.
Also, Hide Armor Prof + Feral Armor. The encounter power of Feral Armor lets you make an MBA vs all adjacent enemies. Which is basically the AP feature of the Neverwinter PP in an encounter power.
Also, Hide Armor Prof + Feral Armor. The encounter power of Feral Armor lets you make an MBA vs all adjacent enemies. Which is basically the AP feature of the Neverwinter PP in an encounter power.
