The initial setup is complicated. Although Kuma has its own CLI, CTL, and they say to use their CLI, if I have to build a generic solution, my personal preference would be to use Helm or another similar solution other than Kuma.
If you have your own library CLI, it becomes hard for others to adopt it. For example, if I have to write some automation, infrastructure automation, I can't just use Kuma. I have to change my code to use Kuma's CTL, which is unfair because it doesn't make sense. It doesn't fit with my current automation structure. I have to do something extra, something additional, which I really don't like.