Hi Jan!
Indeed, as Yoav said, Unicolor makes color transformation based on sheer mathematical operations. It lacks tone mapping and that can lead to over exposed images. The way to tackle this is simply by manually setting the signal somewhere where you feel it should be according to your image and signal response. In other words, by manually adjusting the tone mapping.
Also, you can use the ACES ODT. ACES color science has an amazingly well crafted tone mapping that creates a pleasing tone which was created after multiple case studies and screen audience tests. However, color tools in ACES will not respond to the signal the same way that you are used to on a regular rec709 signal.
Both approaches, as well as the the use of a LUT crafted by the manufacturer are perfectly okay and respectful to the color science of the camera you use. Depending on the project and your needs, you can decide which suits you the best ?
Cheers,
Cristóbal