
A random bit of lore on spirits comes from a level 32 FATE in the Central Shroud, where you fight revenants. The FATE description indicates that a revenant is a soul that missed its opportunity upon death to reenter the Lifestream.
The White Mage quest line delves a bit into the elementals and the Shroud. The level 35 quest text notes that the elementals and the trees (possibly the forest when you consider translation issues) are one and the same. That makes sense when you consider the main scenario quest where the twins comment on the damage done to the Shroud by the calamity and how it will take decades if not centuries to recover. The "elementals" you fight in game are angered or corrupted sprites aligned with an element, but aren't elementals themselves per se, IIRC.
On the topic of Primals, at least according to the Scions, they're all inherently "bad guys" because maintaining their physical form requires a massive amount of Aether that is, as far as they know, consumed. So, if that's true, the Primals are a significant threat to the world, as draining an area of Aether is quite destructive (per the 1.x storyline). Additionally, the tempering process is stated to warp the minds of those affected, making them more like the Primal in addition to turning them into slavish worshippers; the untempered sylphs, for instance, are terrified of this as we discover in the MSQ. These two factors make them the "bad guys" from the standpoint of the Grand Companies, the Scions, and even the Garleans, even if the Primal's motivations may be relatively positive (i.e., being a protector to their worshippers).
EDIT: Made a couple of clarifications and took out something I wasn't sure I read in quest text.
The White Mage quest line delves a bit into the elementals and the Shroud. The level 35 quest text notes that the elementals and the trees (possibly the forest when you consider translation issues) are one and the same. That makes sense when you consider the main scenario quest where the twins comment on the damage done to the Shroud by the calamity and how it will take decades if not centuries to recover. The "elementals" you fight in game are angered or corrupted sprites aligned with an element, but aren't elementals themselves per se, IIRC.
On the topic of Primals, at least according to the Scions, they're all inherently "bad guys" because maintaining their physical form requires a massive amount of Aether that is, as far as they know, consumed. So, if that's true, the Primals are a significant threat to the world, as draining an area of Aether is quite destructive (per the 1.x storyline). Additionally, the tempering process is stated to warp the minds of those affected, making them more like the Primal in addition to turning them into slavish worshippers; the untempered sylphs, for instance, are terrified of this as we discover in the MSQ. These two factors make them the "bad guys" from the standpoint of the Grand Companies, the Scions, and even the Garleans, even if the Primal's motivations may be relatively positive (i.e., being a protector to their worshippers).
EDIT: Made a couple of clarifications and took out something I wasn't sure I read in quest text.

The Freelance Wizard
Quality RP at low, low prices!
((about me | about L'yhta Mahre | L'yhta's desk | about Mysterium, the Ivory Tower: a heavy RP society of mages))
Quality RP at low, low prices!
((about me | about L'yhta Mahre | L'yhta's desk | about Mysterium, the Ivory Tower: a heavy RP society of mages))