As soon as 6.0 was released we switched all future work to KiCad from Altium Designer. This after held licenses for AD going back to P-CAD days (2006, if I remember correctly) and previously using OrCAD and other professional tools. In short, I got sick and tired of sending thousands of dollars per year to Altium for them to burn the cash adding cloud-based functionality nobody I know wants at all. As a result, AD is just piled-on with bugs, issues, inconsistencies and you can pretty much expect every single update to deliver new bugs.
Anyhow, we've done several boards with KiCAD. We are not sorry at all that we made the change. Sure, it could be improved. The good news is, it will. Also, we are happy to financially contribute towards KiCad development because we know it will not go towards bullshit designed to try to sell the company to a larger company (Altium tried to attract Autodesk, and failed --ADSK probably saw the mess AD had become and backed away).
Anyhow, I think KiCad is good for probably 95%, if not 99%, of any board anyone might want to design. I go back to the early 80's for PCB design, which means that I have done some pretty advanced boards with tools that were far more primitive than KiCad.
As a side note, being able to use Python to drive aspects of KiCad is awesome. We've already created a number of useful utilities relevant to our work.