Adding up to Tigore's tips please do note that Army's Paeon reduces not only your Weapon Skill and Auto Attack speed, but also your spells, and songs falls into this category. Effectively reducing the song's recast in 12~13 seconds.

If you don't want your Raging Strikes song to go out of synch you better don't cast it unless Army's Paeon fell off.

Also Sidewinder can't be shot right after throwing a DoT since it'll hit before the DoT applies, but you can put a filler in between so you don't have to manually wait. Peloton covers this problem very easily if you have no use for any other Role Skill.