Allow IFC export overrides of system families/ create a system family category for flooring

[h.bakkerPE58B]

Allow system families such as ceilings to be overriden when exporting to IFC.

We've got a client who demants us to model flooring. Since Revit lacks in a function for flooring with a function similar to "automatic ceiling" we would like to use ceilings as flooring. 
Since ceilings work similar as to how you would expect flooring to behave, it has an insertion point at the bottom layer, allows Room bounding yes/no, hatch patterns show up.

However currently we are unable to export ceilings as anything else (Revit 2022 and 2023).
So my request is, either introduce flooring or allow more export options.

[Simon_Weel]

As a work-around, you can assign a Shared Parameter IFCExportAs (text) to the Floor category. Edit the floor type and specify the IFC type to export that floor.