For context, the shim is just an implementation detail of how containerd runs workloads; some come pre-built by default on some systems (like runc), and others you configure (like kata-containers, or in this case, the Spin shim); and some Kubernetes distros already have built-in shims (or will have soon), like k3s.
Your setup seems to work really well for you (and as a side note, I'm curious to learn more about the kinds of workloads you are running) — I'll note that you can also set the runtime class on a regular Kubernetes deployment / pod spec and you can run the workload like this with the Spin shim (for reference https://github.com/spinkube/containerd-shim-spin/blob/main/d...).
For Spin, we focused on the end-to-end developer experience, and on building a set of tools that take advantage of the benefits you get from Wasm, while integrating with a lot of cloud native tools — while allowing you to more easily build APIs and event-driven functions.
Our goal with SpinKube is to integrate with how organizations run workloads on in their infrastructure, and to make building, distributing, and running Wasm as seamless as possible.
Happy to dive into details for any of the points above, and would love to learn more about what you are running as Wasm.
Thanks!