I agree that I would like the ability for us to reorder our modules without changing pipeline structure. It is something I miss from lightroom, which generally is laid out top to bottom in order of usage: image profile at the top, then light, color, detail, etc.
On the Other Hand…
@Qor I will say this in support of how darktable is laid out now: I think it is helpful for users to always be reminded of how the pixelpipe is ordered, so that they can begin to make logical inferences about where problems need to be addressed. For example, if the module order was totally custom (without changing the order of the pixelpipe), then users wouldn’t necessarily know that going back and changing exposure might require resetting the black/white relative exposure in the tonemapper (like AGX). but with the whole pixelpipe laid out the way it processes, users might be more likely to make those inferences.
This is a gripe I have with lightroom, when I go back to edit something in it: There is no way to visually see which operations are happening when. “Does black point happen before or after curves? Does contrast happen before or after curves, highlight/shadows, etc.” This cause me at least to have to hop around even more, bouncing between different controls in order to overcome the black box effect.