Something else I’ve only just discovered that will significantly streamline my workflow…
It’s possible to create presets that are auto-applied to images but start off disabled. This means that you can override the default module settings but still enable those modules one-by-one. That way you can see the effect of each module in turn and tweak them at the right point in your workflow (without having to manually select a preset each time you move to a new module).
Just set set up the module as you like, disable it, then create your preset.
I knew you could do that with styles - didn’t know you could do it with presets.
Edit: Having used this on a few edits now, be careful because if you compress history stack and go back to an earlier stage, or reset the parameters, you’ll be back to the usual darktable defaults. I think it would still be nice (perhaps I’ll raise a feature request) to be able to change the actual module defaults so that they survive a reset and don’t appear in the history stack until switched on.