Alright from what I can tell there needs to be a different implementation to get pathfinding in 3d space that is acceptably efficient and there seem to be a lot of inherit issues with 3D pathfinding in the first place..
So far it's been recommended that I continue experimenting with what I'm currently working on: raycasting for a robust local avoidance system.
The mian problem with 3d pathfinding apparently isn't that difficult to develop but is
significantly worse for performance in relation to world size which means you'll likely be using a very chunky node graph with low fidelity. The alternative is using point graphs which are custom placed nodes that the agent can path between but it only works properly in a mostly static world where objects aren't moving on top of the nodes that you've placed. If they did, the agent would try to path to them and crash into something dynamic, potentially. This is a huge problem if you're in space with orbiting mechanics or any other number of dynamics.
One trick I thought of was using a smaller 3d graph that follows the agent and updates per frame. Basically bigger, 3D local avoidance since its too expensive to scan the whole game area, or even potentially just to your target.
Another thought was using a low quality point graph over the game zone for major pathing and then again, a robust local avoidance method to handle the up close encounters.
But, either way it seems that the local avoidance is the key. It's somewhat opposite of shooter AI it seems, since plotting the path is the major load, then handling local avoidance is a smaller issue depending on how many agents are involved. If this were aircraft in the atmosphere it would be super easy, locomotion with a target and an FSM for combat behaviors. But in space there are likely many dynamics in the game space like asteroids moving, large dynamic debris, gravity agents, and any solutions have to work and be optimal for 3d use.
So it seems like the solution winds up being: A vague path plot to the target (cheap, large block graphs), a robust local avoidance system(rays, normals, delta positions), and then potentially VO/RVO considerations (velocity of dynamic agents that could hit us) depending on how expensive it is at that point.
I learned a lot today, mostly don't try to make 3d pathfinding work