To divide the responsibilities in a horizontal structure, you may use the Skill/Will strategy. For a vertical structure, it needs to be a gradually escalating one. I request you to view the link to set the guideline for the Purchase - Authority matrix:
How to implement Purchasing Spending Authority Matrix? - Toolbox for IT Groups
For HR, there would be tasks and priorities. Please choose the one nearest to the task while allocating authority. This would speed up decision-making. Here's a link to give you an idea of allocating responsibilities and distributing authority:
HR Maturity Matrix - Human Resources Strategy HR Delegations of Authority Matrix
Once you have delegated authorities, you need to set a limit on how much one leader can decide at his or her level and when that gets escalated. The span and the time frame would be crucial as you need to ensure there are no duplications and bottlenecks.
Please do write back with your queries. Let's design this structure.
Regards,
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