1. What is your idea?
Introduce a new procedure step which exits/stops the complete procedure execution even if the procedure which uses this new exit step is a nested procedure (was executed inside another procedure).
2. What specific problem are you trying to find a solution to, or what new scenario would this idea respond to?
If the current Exit Procedure Step is used inside a procedure which was executed from within another (main) procedure the procedure is exited but the procedure which executed the procedure still continues to run.
To be able to stop the complete procedure process you have to write a value inside a cube in the nested procedure and check that cube in the main procedure which executed the procedure for that value.
If the check is fulfilled another Exit Procedure Step has to be executed to exit/stop the complete (main) procedure process after all.
With the requested new Exit Procedure Step it would be possible to ensure that the complete procedure process is exited/stopped right away without any further logic.