Skill Suggestion - Spectral Blade

Spectral Blade is a self buff that reserves mana - allows you to equip the Spectral blade if you're unarmed.

Mechanical it works like facebreaker. though it shouldn't be locked to unarmed skills only, it is a blade/strike.
I could see this be locked to the same category of skills as claw/swords

How i imagine it would look like: http://imgur.com/6YOi5XS with a more blade ish feeling to it and it should be a chaos effect like ascendant weapon effect http://pathofexile.gamepedia.com/Ascendant_Weapon_Effect

Stats
Reserves 25% of your mana
2% of attack damage leeched as life
________________________________________________
Deals xxx to xxx chaos damage
Critical strike chance: 6%
Attacks per second: 1.4-1.8
________________________________________________
100% chance to poison on hit
Regenerate 10% of Debuff Damage as Life
Hits can't be Evaded(spell)

Scaling this is considered a spell so will scale like every other spell: Spell damage, spell crit chance/mult, crit chance/mult, chaos damage, damage overtime, skill effect duration(posion), attack speed.
The chaos damage and attack speed will scale per level.

Easy implementaion Copy the animation of claws.

Current Ascendancy classes the skill would fit very well
Witch - Occultist
Shadow - Trickster
Shadow - Assassin
Ranger - Pathfinder
Ranger - Raider

I would love to see somthing like this come to life as it would add a good variety to the game!
Melee witch viable? :)