Hello,
I've been thinking for a while on what to store at the Project Settings, objects or numeric/string representations of those objects to set a rule and avoid thinking on this at the future so I want to take the best approach.
On one side storing object representations grants you that what is stored is valid and saves you from doing conversions each time you access them. You only need objects with the attribute.
At the other side storing the numeric/string representation of an object eases the editing of the setting because at the end the user will be entering numeric or string information.
What do you do with this issue?