Wrote in pattern. Somehow packed and short.
From those descriptions, I think that Darkness and Light spells should also cost HP to cast. Spells from all elements, mid tier to high should have a chance to backfire or to hurt the caster and the target. The Neutral should be made to pay extra cast cost of higher level spells from different alignments.
Alignments rewrite:
FIRE: Wildest of the elements, depending on it wielders will, strength and skills. Varying from pleasant warm to source of unspeakable pain. All that just in glimpse of an eye. Used correctly can scorch every obstacle to ash, leaving only burned ground behind. In unskilled hands can be very dangerous to the person using it. This element have the upper hand against Air, but is countered by Water.
WATER: Aside from being really destructive, this element reflects it wielders character the most from all others. If the person using it is calm and confident, the water is easy shaped into desired shape. On other hand, unskilled and uneasy wielder will have hard time casting basic spells. Dominating Fire with ease, Water is relatively weak against Earth.
AIR: The Air element relays on its omnipresent. Being fairly easy to use is the favorite by aspiring mages. On the other hand, to cause mayor damage with this element, the user have to be experienced in using it. In addition to the classical Air attacks, a part of this alignment are also thunder base spells. Being effective against Earth, Air is getting serious damage from Fire.
EARTH: Is a really powerful element if used correctly. Lacks in speed and finesse overcompensates by bolstering force in offence and defense. Unfortunately, not seasoned users tend to lose balance, that is so important when using earth spells. Applying defensive layers not equally, leaving openings and small cracks. When attacking tending to overpower spells that sometimes backfire. The earth element have advantage versus Water but is weak against Air.
LIGHT: Not like the four basic elements that origin from mother nature, Light fuel itself from other source. Gaining it power from the user soul, it drains the wielder, leaving him exhausted. Weak minded and evil people will never be able to cast a single Light base spell. The outcome of such feed, probably would end in killing the person or at best case scenario leaving him near death. But like other elements ,Light have it counter element in form of Darkness.
DARKNESS: Differing from the four elements that come from nature, Darkness is probably the most destructive force that anyone could align with. Tempting with easy to obtain force on the other hand is a cruel lover. Draining the user soul at every single cast, leaving a heavy toll on the wielders body and mind, but the power received in exchange is great and noticeable. The most common users are evil people and weak minded that look for quick gain of strength. But this tremendous force is somehow countered by Light.
NEUTRAL: Not aligning with any element also can be profitable. Being a jack of all trades, the wielder can use any kind of element and isn’t penalized for being countered by certain element type. On the other hand, when being Neutral you can’t master the most powerful spells from the alignments. Also the medium level skills tend to be more difficult to handle and the cast cost goes up.