So, I thought I'd be a little further along with this, but coming up with an order of operations for the production of the environment proved a bit more challenging than expected.
So what am I trying to do? I'm trying to create an impressive and vast cave system which will have a few modular parts. Originally I planned to use the current method of baking high poly cave pieces and rocks, tile and mask the materials, and then just piecing it together. While this method is certainly impressive, It just isn't as organic as I'd like. It is also super time consuming, and at this point I'm pretty sick or making high poly rocks.
My solution? Go somewhat more old school and tile rocky materials across a mesh. The materials will include sculpt work, but the actual cave itself will rely on the geometry for the larger details. This why I can blend 5 materials across a seamless cave piece. I understand if this explanation might not be completely clear, so I'm planning on putting together a step by step.
Below I show a shot of the 5 texture blend material that I can paint on to the mesh with vertex paint. Also there is a shot of a completed cave piece. Only one material is painted on for now, but next on the agenda is painting the cave to see final results.