We are a little off topic; I will finish my thoughts with one more post (then we may start another thread if need be). As I said, I am quite loose with my discussion and might be wrong. My take is this: The transforms themselves are not the problem but the decision process is, not just where the journey ends. Try doing a round trip to see what I mean. Data and relationships are lost; we hope to minimize that where possible.
As for sticking with the camera colour space, I think this would only work if you are careful with your processing, but you would still have to faced the final gamut compression problem. Let me break down what I mean.
The first part of the statement refers to the fact that image processing of any sort would push and pull tones all over the map and also outside of gamut. If your camera space isn’t well-behaved or too wide, colours would become even wilder and more difficult to tame with each step, which is the second part of my statement.
In terms of gamut compression, the more that happens at the end the more detail and tones end up squashed and unnatural. @jdc is a superstar, so I won’t say anything about RT special colour tools. If you look at @Carmelo_DrRaw’s gamut compression, though great, the modules tend to make the images too colourful or odd in some manner, at least in my opinion. If you have a less typical profile, then these problems are bound to be greater.
Your decision to keep the camera profile is just like my decision to raw develop my images into linear Rec2020 working space but not convert the result to sRGB or append a colour profile. Viewing the custom nonlinear Rec2020 in standard sRGB is fine and looks good in my eyes but that isn’t the standard and encouraged approach. Perhaps, your camera has a good profile to begin with. 