- Deleting or bulk changing something? Always use the flag --record. This way, you can refer back to what you changed using kubectl rollout history.

- If you're planning on using GKE, you'll have to expose your apps using Ingress (this way you can use GCP's L7 Load Balancing with HTTPs). However, this architecture has many limits (e.g. a hard limit of 1000 forwarding rules (FW) per project, each ingress creates an FW and k8s ingress can't refer to another namespace), so make sure you use namespaces wisely.

- Try to learn and teach people on your team about requests and limits. If you don't use it carefully, you'll end up wasting a lot of resources. Also, make sure you have Prometheus and Grafana set up, to give you some visibility.

- Setup Heptio's Velero, it's a lifesaver, especially when running in a managed environment where you have no access to etcd. It can be used to backup your whole cluster and migrate workloads between clusters. If, for some reason, you end up deleting a cluster by mistake, it will be easier to recover its workloads using Velero.