Enraging charge is your Arenal opener, use it to run to your target, strike it and get the starting adrenaline you need to start hammering at the chain. It also serves as a Stance Breaker for Flail if you need to.
Use skills from left to right, solid skill chains in there. When you get to Dragon Slash, all your skills should be re-energized for a full second chain before adrenaline needs to be built up shortly again.
Whirlwind Attack is also very usefull, think of it as Cyclone X or Cyclone Sword in this case, good for damage output and building more adrenaline.
Know that Lion's comfort gives you more health back with Tactics so go Sword, Tactics and then Strength.
I would swap out Silver Wing and put [skill]Barbarous Slice[/skill]
I woudnt, since you should be in a stance, either Flail or Enraging Charge, Silverwing does DOUBLE the damage of Barbarous Slice.
Depends... If I don't already have a hero packing Dismember/Vicious Attack or something similar, and assuming that stuff in the area bleeds, then Sever-Gash are two.
Other than that? Also dependant.
The further on you get through PvE, and the tougher foes you face, the higher armour ratings climb. Thusly, in higher-end PvE, I'm likely to opt for Standing or Silverwing over Sun&Moon, unless I'm running something like Conjure or Order on a necro and would get more damage out of the 2 hits.
Also... Barbarous Slice is shit, because Flail is ftw.
And... Save Yourselves! is a Dragonslash attack. Gogogogo.