This opinion is coming from someone who plays with high ping (270-300) and is very very mediocre at PvM:
As it stands completionist cape is very easy to obtain (respectfully, before the realism/EIM people yell at me - your process just takes more time however it is easy. Anyone can afk 200m fish/cook as the most common skills for comp cape)
Should more requirements be added -
Support
Awakened bosses -
No support - why? Very RNG based to gather orbs for IM + ping equalitiy
Completionist cape should signify more than just PVM accomplishments though, possibly adding the requirement of completing all mini games clogs minus GOTR - due to it being RNG Based. Possibly x amount of KC at skilling bosses/CAs completions.
Or some other form of skilling input such as requiring to sacrifice x amount of resource items to obtain the cape etc.