Works best while using Swift Momentum.
Ev 2 - Whirling Flurry, +20% Attack Speed means more damage faster, and faster combo build up.
Ev 3 - Adept Reflexes, +15 Initial Combo plays in to the Level 4 Upgrade by getting you almost half way to the Incarnon Form at the start of combat.
Ev 4 - Swift Transmute, [Reach] 3x Combo and Heavy Attack to activate Incarnon Form means you get the form buffs much sooner to further help with combo build up and overall damage
Ev 5 - Your pick! All 3 can help sustainability of combo and damage.