The beginning is usually best.
I'm going to ask this in a plain yes-or-no fashion; are the proposed Elements; "Fear", "Disintegration", "Hunger", "Shattering", "Poison", and "Fear" naturally occurring Matoran Elements? If not, did some external force cause the change?
What I probably should have asked initially is this; how would a Toa use these Elements in a blast? Based on your definitions, "Elasticity" and "Density" are limited to the Toa's body or, as is the case for "Density", physical contact. "Health" could be a blast of regenerative energy. "Disintegration" and "Shattering" could be blasts of said energy.
Considering most people classify a storm as weather, I'd be more inclined to think that a Toa of "Weather" is capable of doing everything a Toa of "Storms" could and more. But by what you've said, a Toa of "Weather" is really more like a Toa of Atmosphere.
Thank you for the clarification. I miss understood the meaning of "Brimstone". But both could be created by two or more Elements working together; "Magma" created by combining Fire or Plasma with Earth or Stone, "Brimstone" created by combining Air with "Poison". For that matter, so could "Weather" or "Storms" by Air and Water working in conjunction.
These are the problems I see with the Elements as defined. "Weather" or "Storms" Despite what you and Ballom say, these two are the same. "Storms" is just more limited.
"Rahi" This relies on there being Rahi around to control.
"Brimstone" Basically poisonous gas. Which would classify it an evil or negative Element.
"Fate" It's just too powerful to be an Element.
"Density" Any use requires physical contact or is limited to the body, best kept as a power.
"Elasticity" Its use is limited to the body, also best kept as a power.
"Power Scream" This is a power of Sonics.
"Health" I don't have much of a complaint for this except the lack of an offensive use.
"Poison" Any use would require physical contact.
"Electricity" EDIT: Should have had this here to begin with. Ability-wise, it's the same as Lightning. Here are what I perceive these currently undefined Elements to be."Insects" Same basic abilities and problem as "Rahi" except with bugs.
"Moonglow" I'm not sure what this could be other than Twilight. Not really Light, not really Shadow, but something in between.
"Anger" Being able to control or invoke feelings from mild irritation to uncontrolled rage in others.
"Hunger" Would most likely work like the Kanohi Avsa.
"Shattering" Explosions. That's what it is, explosive energy.
"Fear" Being able to control feelings from slight unease to complete terror in others. If I've missed anything or should clarify further, please do not hesitate to tell me. Also I'd like to apologize if I've ever seemed rude, it's a problem of mine.