Darktable is pretty good, I agree. But it's fiddly. Some operations that are trivial in programs like Lightroom (e.g., add a little color noise reduction) can be pretty tedious in Darktable (add at least two instances of noise reduction modules, one profiled denoise, color blend mode, reduce the strength a bit, another wavelet module, blah blah blah). There are, I think, five different kinds of noise reduction modules in Darktable, and it's up to you to figure out what modules and what parameters will work best for you.
If you find a set of parameters you like, you can save them as a module preset and that will be quicker to apply. But even after many hours of experimentation, I was never able to find a combination of denoise tools/settings in Darktable that worked for general purpose NR as well, for me, as just grabbing the slider in Lightroom. In particular I could never identify a module or combination of modules for high-ISO strong NR that didn't color-shift my images.
And I have found that the five basic tone sliders in Lightroom (blacks, shadows, exposure, highlights, whites) are more intuitive and natural than the counterparts in Darktable, which seem (again, to me!) to require more iterative adjustment and compensation to get a pleasing result.
Finally, I think Lightroom does a better job with dust spot removal.
Darkroom is pretty good if the user has sufficient patience to do some significant tinkering, repeatedly. If you just want to get down to the business of photo editing with significant throughput, I believe there are better choices, and Lightroom is mine.
So, even though I have been a majority-Linux user for about a decade, I still keep a Windows installation around just to run Lightroom (and on occasion, Microsoft Office). I run it in a virtual machine so I don't have to dual boot, but I don't necessarily recommend this approach because it has some disadvantages. (To name one: VMware Player, which is free for non-commercial use, has some rudimentary graphics acceleration. It's enough to let Windows do its Aero interface, and it's fine for that. But it's not good enough to accelerate Lightroom 6.)
Anyhow, that's my two cents. I just paid to upgrade to Lightroom 6 because it simply works better for me, and it's worth the annoyance of keeping a Windows installation around. I wish that weren't the case, but oh well.
I'm pretty results-oriented these days, and I have occasionally mentally tossed around the idea of just switching back to Windows to avoid the hassle factor. But every now and then
stuff like this will slap some sense back into me and remind me why I switched away in the first place.