Approver Hierarchy in OPM and SSH best practice is needed

Dears

I Need to know best practice to define approver hierarchy for SSH and OPM which will not get any conflict between them

by the way the Vendor has developed to us Person --> Person Hirarchy to evaluate their empolyees Appriasals.

but in my SSH is different where there is no standard in absense Hierarchy like below  and my Vendor has developed it

based on position hierarchy so I think created this conflict since they are integrated Modules.

Scenarios:

1.       Team Member & Sr. Team Member TO Manager   1 level

2.       Team Member & Sr. Team Member TO Director    1 level

3.       Team Member & Sr. Team Member