This is something that I'd love to see in S3D - the ability to hollow out infill for large models. I've been trying to figure out a way to do it manually, but it's tough. The idea would be to have a separate mesh that creates an inner cavity in the model infill. Attaching a few example images - one from a failed test in S3D and another from Cura.
Cura is able to do it, but i'd honestly prefer to use S3D. The goal would be to have normal outer walls, infill and a single walled inner cavity. The biggest problem in S3D right now is I need the outer shell to be 3 or more layers thick, but the inner hollow cavity to only have a single wall. This is the S3D attempt using multiple overlapping models and individual processes.
Here's the results in Cura - showing exactly what's needed. An outer wall that prints at a lower speed with 3 faster printing inner walls, infill area and a single fast printing inner wall.