Malacath isn't great for sorcs because of our reliance on Crit Surge, you can make it work with something like Clanfear/Dark Deal/Health Regen/Vigor/Rally, but imo, it's not worth losing the gigantic benefit of surge. It's one of the best skills in the game. That passive healing makes them fantastic brawlers.

This is a single target killing machine idea, so it's not really meant for Whirling Blades:

The build is centered around the Draugrkin's Grip light armor set. The set adds a single target debuff to 1 enemy for 6s (9s cd) that increases your damage done to them by 617. The debuff provides an insane amount of extra damage with Flurry (5 hits), Hurricane, dots, light attack weaving, etc. It's all buffed by the 617 and if I remember correctly, damage done buffs like this set and DK's poop fist are buffed by damage done buffs, eg minor/major berserk, or in Sorcs case the 10-1% Amplitude passive.

This is a light armor set so you need to use it as jewelry/front bar weapons, the 2 piece is magicka and the 4 piece is mag regen so you can still get some use out of it as a Sorc, since magicka is pretty important for Streak/Dark Deal. The 3 piece sucks for spell pen, but the set is so strong, it doesn't matter. If you see a Stam Sorc using DW and Flurry spam, odds are they're using this set or have in the past.

With that set, you wouldn't need Whirling Blades because Flurry would end up stronger/same in execute. Con, you have less aoe damage, pro, the set makes you a single target killing machine, your sustain is much better since Flurry is a reasonable cost while Whirlwind is expensive af and you save a slot by having 1 skill for execute and spammable.

With that in mind.. add some of these sets to boost that even further:

(Backbar) Masters DW = Twin Slashes deals 1635 more damage for each hit of the initial attack and bleed. (This + Draugkin is 2200 + damage per hit, there is 2 hits from the initial cast and a dot tick every 2s).

(Body) Way of Fire = When you deal damage with a weapon, you deal an additional 3945 Flame Damage. This effect can occur once every 2 seconds. (Twin Slashes will automatically proc this on a target for you, the dot lines up with the 2s cd of the set).

(Alt Backbar for more mitigation) BRP DW = 6% damage done and -6% damage received, you should use Quick or Deadly Cloak regardless, but this is a nice option if you want to survive more while also increase the damage you deal (Buffs Way of Fire and Draugrkin's Grip 617 damage done).

(Alt Body, Craftable) Dragon's Appetite = Increase your damage done to Bleeding enemies by 225. Dealing non-Bleed damage to Bleeding enemies generates a persistent stack of Dragon's Appetite, up to once per second. After 10 stacks you consume Dragon's Appetite and heal for 6415 Health (3k in pvp before any healing multipliers).

Dragon's Appetite has the same effect as Draugrkin, but only at 1/3 the value and with more stamina related 2-4 piece bonuses and the small benefit of a small heal every 10s. This set is a way you can double down on making Flurry/dots/Hurricane, etc tick for even higher values for +842 damage to all your ticks. Start a fight by applying Twin Slashes then proceed to Flurry them to death. If you use the alt weapon below, start with that then Flurry spam and it has the same effect.

(Alt Backbar) VMA 2H = Adds 1190 Physical Penetration, Dealing damage with Critical Charge causes enemies to bleed for 10032 Bleed Damage over 5 seconds. Why this set instead of Master DW or BRP DW?

1. Having 2 of the same weapon type may feel a bit annoying by killing some of your build diversity.
2. Maybe you want Rally, but I personally don't use it on Stam Sorc with Surge/Dark Deal/Vigor.
3. Having a gap closer (Although streak is kinda that already, you can use that as an escape).
4. Stampede + this set is insane, if you're not aware. Stampede is an aoe attack that places an aoe dot on the floor. The dot sucks, but serves 2 purposes. Firstly, anyone who touches the dot, will proc your enchantment when you're on your front bar, so you'd want to use an Infused + Weapon Damage glygh or Fire/Poison Enchant. Secondly, the set effect of applying a 5s dot ticks once a second and will refresh ANY time someone touches the dot, even on your front bar. So this set at base should tick for 2k bleed damage a second, but because of Draugrkin and Dragon's Appetite, it will tick for 2.8k a second.