I'm running k3s in production. K3s has hooks to setup Prometheus, autoscaling (for spot instances), etc.
I don't see all of these in microk8s. I'm not sure if this is on the roadmap.
I'm also not sure how customisable microk8s is. We run k3s with haproxy ingress (which is not the default) and calico for network (again nog the default)