Selecting elements based on different properties is fundamental to CAD/BIM workflow and the intuitiveness and generality of the criteria expressions makes it one of AC most potent functions.
Currently criteria expressions have to be created for each use (find and select, find and check, graphic overrides or scheme settings) which is not only inefficient but the different interfaces means slightly different and limited ways to do it.
Instead I would like to see a dedicated manager for creating criteria expressions which are globally available for all current and future (hint: visibility) uses. The interface can then be built with full focus on the expressions paving the way for realising their potential.
Some starter points:
Make it possible to organise (name/tag/description) and search expressions.
Make it possible to create variants of expressions with different values - removing the need for multiple independent expressions for e.g different stories, measurements, systems et cetera. Perhaps by defining variables which easily can be set when using the expression.
Make it possible to create compound expression consisting of multiple expressions - reducing the need of repetition and long expressions.
Make it possible to evaluate expressions in the model rendering a list of the extension.
Make it easier and quicker to create expressions. Currently criteria first has to be chosen in the list, then the operators set in the editor using the mouse, then values set in the editor once again using the the mouse. It should be possible to do in one go without using the mouse. More command like: search and select criteria <press enter> search and select relevant operator <press enter> search and select or enter value <press enter>.
Finally it should be noted that criteria expressions are an obvious stepping stone to the introduction of AI into AC the form of natural language processing turning prompts like "all doors on the second floor with a width of 900" into expressions. Natural language prompted selection - the marketing team won't break a sweat.