So heres the conduit! I'm very happy with how this turned out.
The conduit as a class is best described as a "Con Based Martial with spellcaster aesthetics", since, mechanically, it fills a martial role, being a class that doesnt use resources, with a primary party focus on dealing damage, while flavor wise, it goes around slinging blasts of energy at people.
This class mechanically is very much based on the warlock of 3rd edition, with flavour and some mechanical inspiration from the Kineticist of Pathfinder 2e.
The two core design elements that I tried to stick to with making this were 1. Being resourceless and 2. Customizability.
For the first point, none of the class features are limited in uses per day. No feature adds an additional resource for the player to track, nor uses spell slots nor etc. The closest it comes to a resource is its Exertion mechanic, where certain things tire out your conduit character. Though, this serves less as a resource, and more as a temporary debuff, reducing your damage output whilst its in effect, before being easily removed.
The second point is customizability. The first element of this is subclasses. Of course, theres the variety of subclasses to pick from, but notably, is that unlike other classes, you aren't bound to picking just one subclass. From 7th level onwards, whenever you reach your subclass feature level, you can choose to continue advancing in your subclass, or you can take the initial features of a different subclass. This means while you can do a more traditional route of going "I'm the lightning guy, I'm taking lightning every level", you can also do an avatar style "Master of 4 elements" and have 4 different subclasses by level 20. Mix and match them as you like, be the "Fire and Lightning" person, be the "I control water mostly, but also a little bit of ice", combine your elements and so forth.
The next part of customizability is in talents. Talents are very much your classic invocation style feature, of which there are... like. 60 of them at this point. But! Theres a lot of variety in what they do. While you have your choices of ones that give additional powers, like flight or teleportation or whatnot, a large bulk of them are dedicated to one thing: Reshaping your elemental blast. Go out there as a fire guy and blast people with fire, then turn around and literally explode everything around you in flames, then focus your blast into a roaring line of fire that pushes everything within it towards you, and then rush the last man standing with a spear made of literal fire.
The talents are designed around not just being able to reshape and modify your blast in a bunch of different ways, but you can combine them together and do cool stuff.
Because at its core, I wanted to design this class to fill a very specific style of fantasy, and thats of the type of magic you see in some settings where its just "I control this one element", and then from that the mage turns that into a billion different things.
A fire wizard will say "I can cast fire bolt, fire ball, and scorching ray". A fire conduit instead just has an elemental blast, but they can turn that elemental blast into a bolt that is hurled at one person, or have it explode into a ball of flame, or split it into multiple beams.
Its very much a creativity first subclass, and thats whats behind its capstone! The capstone is all of this at its epitomy, the ability to freely reshape your elemental power (By freely, temporarily learning talents) into whatever form you imagine.
Hell, customizability is built even into the very core of its flavour
I hope you guys enjoyed reading this class as much as I enjoyed writing it and as much as I enjoy talking about it <3