Integrating Nomad with Vault and Consul is super easy and allows you to provide secrets, configuration and service discovery to the application with the right layer of abstraction, the application should not be aware of the scheduler it is running on. Cloud auto join allows super easy cluster config. Job files are declarative.
Yes, Nomad does not have all the features of Kubernetes, but we take a different approach believing in workflows and the unix phillosophy of a single tool for a single job. A fairer comaprison would be to comapare the HashiCorp suite of OSS tools to K8s, Nomad, Vault, Consul, Terraform, this gives you capabilities to manage your workload both legacy and modern.
Looking at doing Vault in HA leads people to look at Consul, which leads to Nomad. (Consul uses a consensus protocol for service discovery and I think that will be interesting for the next generation).
Last year, K8S had already captured the center of gravity, and it took a while for the rest of the dev community to catch up.
I think this year ia a lot of shuffling as the survivors settles into orbit around K8S. There is a lot of interesting innovations up the stack once orchestration is de facto standardized.
K8S still hasn't solved the stateful workloads, though it is introducing a lot of primitives to support those: controller hooks, third part resources, on top of which Operators can function.
I think we will see a lot more innovations as people create Operators. That can include anything from stateful loads for specific distributed stateful loads, to things like intrusion detection, ML-driven autoscaling, and so forth.