I believe you can already add a temperature controller for a heated chamber in the Temperature tab of your process settings. We have many printers that already utilize that feature with S3D. If you need help setting it up, feel free to email our team directly at the link below and they can assist you:
https://www.simplify3d.com/contact-us/
For "shell overlap percentage", I think that is typically accomplished by adjusting the extrusion multiplier for the extruder that is printing the shells. We also allow separate extrusion controls for top layers, bridging, supports, etc.
For overhangs, if you enable the "apply bridging to perimeters" settings, then any perimeters that are on an overhang will be identified and you can set a separate fan speed for those in the process settings.
Hope that helps!