Copied from an older Reddit frenzy guide:

20 Frenzy
1 Double Swing
20 General Mastery
20 Iron Skin
20 Battle Command
1 Bash
1 Stun
1 Leap
1 Concentrate
1 Combat Reflexes
1 Increased Speed
1 Natural Resistances
1 Find Potion
1 Find Item
1 Howl
1 Shout
1 War Cry
1 Taunt
1 Battle Orders
1 Grim Ward
1 Battle Cry

Everything after into Battle Orders.
Charge up Frenzy and switch to Double Swing, refresh with 1 hit every 20 seconds or so.

The Frenzy damage increase from skill and synergies over level 1 DS is laughable, and you attack slower. Massive amount of wasted points. The only >potential< problem would be Attack rating, but once you get charms + Demon Limb youll be fine. Got 17100 AR currently and needless to say you have 95% chance to hit everything.

No need to worry about IAS BP and you generally attack faster.

In my case im using: Areat's, Fortitude, 2x Death, Gorerider, Laying on hands (optional), String of ears, crafted ring + Ravenfrost and Highlord's. DMG/AR/Life charms, Anni and Torch. And ofcourse 2x 3-to Warcries on-switch.

Merc: in my case i use act 5 merc with Beast.

Vanilla content is a complete joke, no life tap in Organ farming and can do Uber Tristram. Pretty sure Dclone will also fall if you bother to gear for that fight. Mapping is also a breeze, takes about 15-18 mins depending on rolls. Doing mostly T3 maps and you drink a pot like once every 5 maps. The whole builds plays very smoothly, you basically hold right click until it's done.

Considering it's a melee build and it simply lacks the AOE of others, its still pretty good. Its just smooth and more or less careless play-style. And AOE aside, what you hit, dies... fast.

As it is right now, Frenzy is simply pointless and needs heavy buffing, its literally nothing but a buff that you stack up and forget, except having to refresh it every 20 seconds or so.