The Peleahn one is obvious - flames burn, so anything to maximise light output of a flame would do.
Fyvria, you got that right too. Bioluminescence is the key to Fyvria light spells.
Odivshe is problematic, because it deals with the opposite of light. I'm imagining that some sort of spell to concentrate lunar light from Yael, or using shadows to concentrate light.
Jmorvi, there could be some sort of spell to work on glass, turn it into Bob Shaw's slow glass (which absorbs light and releases it over time). And Savorya, I dunno, glowing runes or something.
A Grey Mage could create a neutral light spell, using Lyahvi Principle and treating it as neutral, but all the other Convocations would suffer a penalty to cast their spells with Lyahvi Principle - Fyvria, most of all.

Interesting topic! I like the idea of Jmorvi capturing and releasing another element - quite fitting, I think. I wonder whether an object element penalty would apply; I'm thinking 'probably'...

For Odivshe I wonder if adapting sight to see in the dark would be feasible. The object element if casting on another would be Fyvria - secondary, so not too bad - but a self-casting would be on Odivshe and enhanced facility in the dark doesn't seem totally outside the element (making the fluid in the eye a vision booster?). Fyvria, too, might be able to adjust eyesight to see better in certain lighting conditions, but not without any natural light at all (which might even be possible for Odivshe?)

Savorya is tricky, but you might have some success focussing on the information content rather than the actual visual senses. A spell to convey the meaning of what the eyes would tell you, rather than give literal sight; this might be quite challenging to get used to!

Yeah, there'd be a tertiary convocational penalty. But I'm guessing that a perspicacious Jmorvi would use a crystal, or craft something in glass or ruby (ruby is a stone, too!) to offset that penalty to some extent.

It would 'only' be a secondary penalty, but yeah. Hmm, that might even feed into the value placed on gemstones, and ruby in particular - they combine essences of Lyáhvi and Jmôrvi in one object. That might have relevance to arcanists beyond the Shèk-Pvâr. There are also spells such as Infuse that might be developed to prepare objects for just such usage.

Similar features can be found elsewhere - bioluminescence (Fývria/Lyáhvi), alcohol and naptha (Odívshè/Pèleáhn) and so on.

Beam of Nolar (Lyahvi).
The first laser was made from a ruby crystal.

On Terra, yeah - but all magic is hard there anyway.

Who's to say Nolar didn't stumble upon his beam by experimenting with pumping the energy states of atoms in a ruby crystal?

Absolutely no-one! As a Shèk-Pvâr, however, he probably wouldn't have thought about it in those terms, since they don't appear to fit with Pvâric philosophy. That possibly marks an interesting divide in p-Hârns, actually - the divide between those that Terran scientific understanding is essentially the "truth" of how things work and Pvâric philosophy is a somewhat inefficient though freeing way of looking at the world, and those that assume that Pvârism is actualy closer to the "truth" - at least for the specific familial world of Kèthîra.

So being a Lyáhvi Mage creating light is rather obvious to do this. A creative thing you might consider is not to be seen self due to the normal light. Iluminating a dark area with invisible light (technically terran say ultraviolet light) seems to be also a thing what a Lyáhvi could do.

- For Sàvôrya it's definitivley not creating light. Despite that glowing runes as a possible lyáhvish side effect for sàvôryan spells could do the trick. But creating knowledge how it would be perceived if it is illuminated seems to be the plausible and easier way. The caster would not be detected because he is still in the dark...

- For Odívshè it's a spell that ignores darkness. This is easily manipulating a primary Odívshè element. (Destroying Darkness with something based on the Destroy Spell (MC VIII) could also be considered but we're speaking of a rather high level here...) So rendering oneself imune to Odívshè Elements sounds rather plausible.

- For Jmôrvi I would primarily think of hot iron which usually glows. As this seems to be an metallic adjective it can be manipulated for creating a light source. (In my opinion that's what Krazma did to his penny of course). That is the easiest approach. Overcomming darkness without being seen is hardly possible. Here I would allow spell researches with magnetic and/or electric conductive properties of metal to figure out that living beings have a kind of electromagnic field. Another possible thing is detecting neglible metal parts of bodies (iron in blood, natrium in salt, etc.) or in dust to enable a kind of vision. In any case to have a useful spell, this would have a high level indeed.

- For Fývria fireflys' bioluminescence might not be known to all Shek-Pvars. But a bats ultrasonic sense or eyes of cats or owls might be considered as well to overcome darkness for a Fýfrian SP too. Especially since it's not pointing out the existence of the caster compared to fývrian light effects.

- Peleahn SP simply create a flame. Flames usually create light depending on their exact description (i.e. blue flames do usually not illuminate very well). A common side effect for fire is light. But a more creative approach is already existing with "Eyes of Nîyar". If the caster don't want to be seen an active infrared vision would be totally perfect for this convocation.