So heavy attacks are pretty boring and ultimately feel unrewarding. So i was just kinda thinking about ways they could be more fun and rewarding and i came up with an idea. You could turn heavy attacks into multiple hit combos over a 3 sec duration. Each hit in the combo would apply an effect stacking in duration based on the number of hits. So lets start with staffs.

Staffs: All staff heavy attack would be a drain similar to how resto staff currently functions.

Resto staff: Damage target over 3 sec. Gain a Heal over time on self and one ally in a small radius around the target that ticks each sec that you channel your heavy attack and up to 3 sec after you finish heavy attacking. This duration is based on how long you channeled. Double the duration of the HoT after effect to 6 sec if you fully channeled your heavy attack.

Destruction staffs: Damage target over 3 sec. Apply current staff element status effect to target each sec that you channel your heavy attack and up to 3 sec after you finish heavy attacking. This duration is based on how long you channeled. Double the duration of the status effect after effect to 6 sec if you fully channeled your heavy attack.
Fire- Apply the burning effect dealing damage over time.
Lightning - Apply the Concussion effect reducing targets damage.
Frost - Apply the Chilled effect reducing targets movement speed.

Stamina based weapons: Multiple hit combo over 3 sec. Two Handed and One Hand and Shield, and Bow hit 1 time per sec. Duel wield hit 2 times per sec.

Two Handed: Damage target with a 3 attack combo over 3 sec. Apply a status effect based on the type of weapon you are using. This status effect applies to each attack in the combo and up to 3 sec after you finish your combo. This duration is based on how many attack in the combo you landed. Double the duration of the status effect after effect to 6 sec if you landed every attack in the combo.
Sword - Gain increased damage buff
Axe - Apply a Bleed to target
Maces - Gain increased armor penetration buff

One Hand and Shield: Damage target with a 3 attack combo over 3 sec. Gain a damage shield. This shield stacks for each attack landed in the combo and lasts up to 3 sec after you finish your combo. This duration is based on how many attack in the combo you landed. Double the duration of the shield to 6 sec if you landed every attack in the combo.

Bow: Damage target with a 3 attack combo over 3 sec. Apply the poison status effect and damage over time. This effect applies to each attack in the combo and up to 3 sec after you finish your combo. This duration is based on how many attack in the combo you landed. Double the duration of the status effect after effect to 6 sec if you landed every attack in the combo.

Duel Wield: Damage target with a 6 attack combo over 3 sec. Apply a status effect based on the type of weapon you are using. This status effect applies to each attack in the combo and up to 3 sec after you finish your combo. This duration is based on how many attack in the combo you landed. Double the duration of the status effect after effect to 6 sec if you landed every attack in the combo. These status effects can stack up to 2 times if using 2 of the same weapon type or can apply 2 unique status effects if duel wielding different weapon types.
Sword - Gain increased damage buff
Axe - Apply a Bleed to target
Maces - Gain increased armor penetration buff
Dagger - Gain increased crit chance buff

This speeds up the responsiveness of using heavy attack. The animations applied to these can make them look more fluid and less hey I'm winding up for a big hit. The effects added to the heavy attacks make them great for fitting into rotations. Landing a full combo or drain can still give resources back as well. Makes for less spamming of 1 button over and over and adds another layer to weapon choice.

If you have any feedback or idea's please feel free to share.