Hi Ibrahim,
you're welcome.
1) Concerning the creation of a new method to check if the dynamic method already exists... The exporting parameter "E_STR_EXCEPTION" of the MF can give us some usable details. But concretely, the MF does not re-create the method if this one has already been created before. Anyway, no dump, no error if the method has already been created 
2) Regarding my point of view concerning the OO Utilities, I prefer oriented my work on dynamic framework based on several Design Pattern and let the database (Customizing table) far away of my code. I can not give you more and precise information for the moment, because I am exactly working on a Workbench Framework, but if I may suggest you, try to store your method or some Generic Class Behaviors in a Dynamic Global Class instantiable with a combination of Interfaces and Heritances for the childs class.
I hope to finish up this part of the framework quickly and share it for the others. You will know exactly the purpose of this current topic at this time.
Wish you a great day.
Rachid.
ps: not active, because maybe you missed "ENDMETHOD."
i_str_code = 'ENDMETHOD.' .
APPEND i_str_code TO i_tab_code .