We need to be able to determine our team's actual capacity, as well as the related work load.
 
We are looking for a feature similar to Microsoft Azure DevOps' capacity feature. 
See here (the "Review Capacity Charts" especially).
 
Main features:

1. Be able to set each team member's capacity, individually.
2. (Nice to have) be able to set days off for the entire team
3. Be able to graphically see workload by team and by each team member.
4. Be able to see what contributes to the above mentioned workload, task wise.
5. Be able to calculate workload by either tasks/subtasks/user stories (default: sub tasks).
6. (Nice to have) be able to set different types of roles (e.g. developer, QA etc.) and see workload by role.

It seems that there is a rather basic work load feature in Jira, but it doesn't work with sub tasks.
 
How can we enable such features in Jira as well?