Miscellaneous items like education, vacation etc can be entered/planning from resource calender as non-working day by their resource managers. This allocation reduce resource capacity. Public holidays must be entered main PPM calender. So the resources' calenders can inherit these as non-working day.
Another way like your solution, create a project which manage by HR. This project can be a yearly education plan for an education or every single education can be a project. Resource load should be come from work plan. Other items can be still planning from resource calender like vacations.
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IT Governance Professional & PPM Solution Architect