Any apps you have as complications will drain your battery. Even if you turn background app refresh off (which isn't necessary), apps set as complications will refresh in the background and run continuously.
Apps set as complications are far more relevant than the settings for wifi, background app refresh, auto workout, and fall detection. I have all of those on and get 2 to 3 days battery life.
I would take a hard look at third party apps and complications rather than spending time reducing the functionality of your watches by turning of settings that have a marginal affect on battery consumption.
I turned off Fall detection and my usage went down considerably. It’s now at 4 hours with exactly 24 hours standby with the battery at 46%. It’d usually be over 6 hours of usage by now. Though I must say I switched to Infograph modular last night and I use it for sleep tracking.
I’ll let it drain completely to see the actual mileage.