Raw Therapee is an excellent piece of software, and at the price (free) it's even better! Although I found it a little difficult to use at first, once one has learnt how to get the best out of it, the results are - in my experience - generally superior to any other Raw converter that I have tried. I haven't tried the Darktable program that you mention - it doesn't seem to be available for Windows. Obviously, most of the best-known imaging programs are also full-featured editors in addition to being Raw converters, and as such, have a great deal more functionality than RT. However, specifically for quality
Raw conversions, I certainly favour RT.
Thanks for posting your superb flower shots - BTW, the RX100 also did a great job here (as did the photographer!)...