Enable relative searches, e.g. 'point size more than 10 pts' or 'space before less than 6 pts'
You can use the Find Text and Find Grep features to look for certain constant values, e.g 'point size 12 pts', 'tracking 75', 'space before 6 pts'.
But it's not possible to search for relative values, e.g. 'point size less than 12pts'. And it's not possible to do negative, e.g. search for certain text in paragraphs that do not have a certain paragraph style applied.
These features would make it much easier to find text with missing or incorrectly applied formatting, and generally would mean that the search scope can be specified more flexibly, which in turn means that InDesign's search feature would become even more powerful.
There have been feature requests for negative values (see links below), but not for relative values. I mention the other links here to consolidate these similar requests.
Find searches for anything that is NOT the term. eg. Find NOT 12 pt will select text that is not 12pt
Find all except this Paragraph or Character Style
Find/Change "negatively" on a paragraph/character/object property (i.e., look for a style set to anything BUT 13pt)