Like all of Hashicorp's tools, they are more complicated and error-prone than they first appear, because they stuff too much functionality in one binary. But it does let you implement one piece at a time, so you can make incremental improvements as you need them.
What do you think is "too much functionality in one binary"? With Nomad I feel like the opposite is true: Nomad is just a workload scheduler. If I need service discovery I can add Consul, if I need secrets management I can add vault. Honestly curious by what you meant exactly and how Kubernetes does it better / easier.