Which helps more against cam surge: adding timing in the low-RPM spark tables, raising minimum idle airflow, or dialing in the VE and MAF tables?

Here is what the documentation says. Each point links to its source; tables and names vary by computer, operating system and tuning software.

• LS Gen III/IV; 1997-2013: A hotter cam raises airflow rates across the range, so fuel flow must rise to match; the fuel curve ramps more steeply and peaks at a higher RPM than the stock cam's fairly linear curve. (SDS EFI)
• GM P01 0411; Gen III LS: A large cam typically lowers volumetric efficiency at low RPM and raises it at higher RPM, so the stock idle-region VE values become wrong after a cam swap. (LSX Magazine)
• Gen IV LS, Gen V LT: An aftermarket cam in a delete build requires adjusting idle airflow, fueling, spark, torque modeling, and other drivability tables, beyond simply switching deactivation off. (LSX Magazine)
• LS Gen III/IV; 1997-2013: LS ECMs carry two spark tables, High Octane and Low Octane, and the ECM continuously blends its commanded spark timing between them based on how much spark knock it detects. (LSX Magazine)

More in cam tuning, or build a checklist for your swap with the tune checklist tool.