since the relations interface and the relations one can use in the model did not get updated substantially during the last decades, this one is to propose a completely new style for this functionality.
Instead of inventing a new type of tool-set or using some existing basis and sizing it down to use in Creo let's use Jupyter Notebook format as relations.
This would mainly result in having a user interface like a beautiful Jupyter notebook editor and the Jupyter engine for running the equations.
As a result, less lock-in to vendor specific tools AND more and easier functionality for the users would allow for much more productivity because the Jupyter notebook format is already widely used within science and engineering. Since the format specification is being licensed under BSD no license costs would add up.
One could finally talk to the physicist who invented the parts functional geometry, show the Creo window with the equations via screen sharing, and they would understand what's happening inside the model! How great is that!?
And another aspect is that people born after the year 2000 tend to dislike the current relations editor style, to express it in a polite manner.