Perhaps the formulas could have an option to filter by skill-required. This would make it easier to, say, work on a specific skill, or find a particular similar sounding product that works differently (transmutation, for example).
Perhaps the formulas could have an option to filter by craft class. This would make it easier to work as a lairshaper, or mason, or some other class, and only have to look through recipes based on skills appropriate to the class.
It would also be nice to have a sticky option, so that the filter is maintained even after closing/reopening the window.