The ENO should support Tshirt sizes when allocating resources for namespaces it manages. 

The sizes should be S, M, L to begin with, and they should specify hard resource limits for the namespace reservation.

• S size: The resource limit ranges should be defined based on the minimal amount of resources required to deploy a service.
• M size: The resource limit ranges should be defined based on an extra 50% amount of resources compared to size S
• L size: The resource limit ranges should be defined based on an extra 50% amount of resources compared to size M

These limits are only a estimation and must be tuned out of trial and error experimentation, measuring a reference application. We can use RBAC, Ingress and Advisor as references to set the S size.