Looking at the Reaper.
Listed as a race, they have aspects and a flavor that better suit it as a class. Reapers choose a Realm with which they are tied to, effectively birthed from. This Realm then grants them several benefits specific for the Realm. Their generic base benefits are a summonable? Weapon unique to them, that grows in power with them. Said weapon can also launch a, once daily, blast of Realmic Energy at a target.
Just an opinion....this, to me, looks like a Warlock. Powers born from a source, a weapon that is always available. The only thing missing is the spells....which can be accessed by ANY class if so chosen(some restrictions may apply ;) ).
My original character idea was to create a class that accessed Shadows. This was before purchasing and gaining my copy of Veil of the Void(Don't wait, buy now...you won't regret). That has since changed after looking through the Veil as a whole(Looking through the Veil...that needs to be the title of a board. Just saying). I want to propose a new Class that will work with ALL of the Reapers. A class that will double down on their ties and truly make them a force to reckoned with.
I give you the Bourne.
Merriam-Webster definition is Boundary, Limit and Goal, Destination...little confusing there. Synonyms is where the application becomes clear. Dream, Design, Intent, Intention...Purpose.
The Bourne will be an Arcanter style class that will delve deeply into their Realmic ties, learning how to better utilize those ties. Each will have their own Novice, Apprentice, Adept and Magus level spells. The benefits will expand further than previous listed, expecially expanding upon the Weapon and Reanding Strikes. Each Bourne will have Sur-Title, listed below:
Order: Patternbourne
Reflection: Glimmerbourne
Shadow: Shadowbourne
Arcane: Spellbourne
Presence: Truebourne
Adareth: Primebourne
I really like the idea of the Reapers transformed into a class. The idea of a Realm-born class really appeals to me, especially with magic in the Veil of the Void universe working the way it does. Giving other races the ability to connect to a realm that way is something I hope we dip into for future releases, especially where the magic of other realms are concerned.
Opening these realms use to non-Reaper races? That sounds great. The fact that this class could also just make a Reaper's inborn qualities even more awesome is a bonus--or give them a secondary Realm to pull from. You could have a Bourne-class Order Reaper with a Reflection spec, for example. Wild.
Of course, this assumes using the "Prime Universe" with the Reapers intact.
As for the ideas for Adareth Channel ability: Adareth is the Realm where Life lives, and Ether is the magic that comes from Endscape, the domain of Death. An Endscape Bourne (there are no Endscape Reapers in the Core Rulebook... but, as Trever is fond of saying, anything is possible here) would probably channel an Ether Blast. They might even be able to use the same spells as the Mechromancer, if you weren't keen on creating an entire new library of spells for all six specs.
My inclination is that an Adareth Reaper would channel Life's power, or the same power that a Naturalist channels: Natura. This appeals to me because the Natura spell tree is limited to the Naturalist class. Half of me likes that exclusivity, but having another class that could draw on that spell tree (because of an intense connection to Adareth) makes a ton of sense. There are even a few spells that give the healing effects you're looking for (including a Magus-level "Phoenix Down" type spell). Having a parallel Naturalist class that is equally connected to Adareth sounds fun to play with.