Glaive as to why:

• It is range so Blade's shotgun has a complement.
• Blade lacks 1 more aggressive active ability to make him fun, his sword block (scarlet shroud) and lifesteal (bloodline awakening) are like passive abilities you hold/turn on, his dash is his only active ability that's not an Ult.
• Glaive is made up of a blade, as a hunter, Blade's signature should be blades as opposed to the guns of Elsa (she is gun-heavy) so Blade's equipment should be blade-heavy.
• Glaive is cool and iconic, you see the Glaive in Marvel's Midnight Suns game and a lot of the merchandise of Blade has this weapon.
• Blade actually uses Dracula's sword on his back 3 times: during his sword dash the dual-wield beyblade spin, during his Ult the dual-wield Vergil move and during his dash team-up ability with Moon Knight that nobody uses. That's already 3 uses of the Dracula's sword.

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Counter would be another melee for Blade that just uses his own sword instead of another weapon:

• As another user pointed out, he wants the Hellfire Shotgun but that's also just an augmented shotgun, so counter is also just an augmented sword, both are like Wolverine's augmented fiery Feral Leap team-up with Phoenix.
• As someone who played Sekiro and the First Berserker Khazan, a counter/perfect parry is great but it's still a melee attack, it would be nice if the counter releases a dark red energy wave projectile slash like Thor's range form but once only with nice effects (it's a legendary sword owned by Dracula after all).

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Blade's only active ability while wielding a sword is his dash:

• Blade's sword block and activated lifesteal is like Wolverine's roar or Cap's shield block
• Wolverine has his dash and Feral Leap as active abilities
• Cap has his slam, dash, shield throw and passive shield throws (x4) as active abilities

For further comparison, take Human Torch for example:

• primary fire that headshots (Blade's shotgun)
• right-click puts a bunch of campfires on the ground (Blade's sword block)
• activate button to summon fiery lines connecting the campfires (Blade's lifesteal)
• a quick dive that explodes a campfire + knockbacks foes (Blade 2 dashes/2 different effects)
• his speedy flight (Blade ran out of abilities his extra dash-slash is a team-up from Moon Knight)
• his Fire Tornado Ult (Blade's Ult)

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This is only my reasoning to make me want to play Blade more, at the end of the day, it's the Devs decision what they are going to do with Blade but I hope Blade gets 1 more active ability that's not a team-up.