Human sailors in Azur Lane's combat environment

What roles could human sailors retain in Azur Lane if more had survived?

Very few combat roles are envisaged; limited dockyard or logistical work is the main possibility.

If more human sailors had survived in Azur Lane while Kansen emerged as they do in the story, ordinary humans would still face a combat environment dominated by much more powerful weapons and beings. Placing them aboard fighting ships would expose them to an environment they cannot match. Dock personnel or logistical work are possible remaining roles. Even those possibilities are treated as limited because the Kansen do not appear to need much human support. The reasoning applies to Azur Lane's fictional setting.