subjective:

(1) service functionality: single responsibility

measurable:

(2) code volatility: how often does code change

(3) scalability and throughput: scale/throughput, startup delay

(4) fault tolerance: continue working if one part crashes

(5) access control: separate sensitive data to a separate service

(1) service functionality

what is "single responsibility" is subjective...

(2) code volatility

(3) scalability and throughput

scalability (requests / minute)

startup time "mean time to startup (service)"

(4) fault tolerance

(5) access control