General consensus on these feats is that they are turkey, as they lower your DPS in almost all circumstances due to activation and animation times. Cleave is a FB pre-req, other than that there is no real reason to take it.
Here are my suggestions for rework of cleave feats
Cleave
Passive:
When you strike a killing blow, you enter a cleave 'stance' and gain an additional +2 to hit and damage (stacking) for 10 seconds.
If you strike another killing blow within that time frame, the timer simply resets to 10 seconds (still +2, damage and to hit won't stack on each other)
Sub-suggestions
-To give it more utility for long drawn out fights, possibly have it activate as a clicky as well (like madstone boots). Say 60 sec cooldown.
-Have it scale with level, extra dmg for two handed fighting (vs twf or s&b)
Supreme Cleave (FB)
Passive:
Adds 4% doublestrike chance when in 'cleave' stance
Great Cleave
Passive:
Increases cleave bonuses by 50% (i.e. duration, to-hit & dmg, and double strike if FB for SC)
The pnp version of the feats allowed you to take down multiple enemies fast - this was the rationale behind my suggested changes, getting combat bonuses on striking killing blows.
Whirlwind
Active: cooldown 60 sec
For 20 secs your chance to doublestrike increases by 5%. Each two additional mobs within 25' (haste radius) of you at the time of activation increases the doublestrike chance by 20% (to a max 85% - this would require you to be 'surrounded by 8 mobs).
As in pnp, the feat should increase in power the more mobs you are surrounded by. 85% doublestrike chance may seem imba, but keep in mind the duration is limited, requires specific conditions regarding mobs to be met and the pre-req feat cost. I think the feat as I've wrote it has some nice tanking synergies.
any comments or other suggestions?