I find by far the most useful to be the Self Study Script combined with the Additional Filters Script that way I can review my leeches and items I get wrong in reviews or the lesson I have just completed to better reinforce it. Also the Self Study Hide Info Script. Honestly I find the self study scripts to be soooooo helpful, but do not abuse it to the point you get a review correct only because you studied it too recently in self study.
A simple one but one I think should just be in WK vanillia is Show Specific SRS Level in Reviews Script which esentially just tells you what apprentice or guru level that item is when you get it right or wrong in reviews. Honestly I don’t know why this isn’t already in WK.